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1.
J Exp Biol ; 224(23)2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34755862

RESUMO

Lantern bugs are amongst the largest of the jumping hemipteran bugs, with body lengths reaching 44 mm and masses reaching 0.7 g. They are up to 600 times heavier than smaller hemipterans that jump powerfully using catapult mechanisms to store energy. Does a similar mechanism also propel jumping in these much larger insects? The jumping performance of two species of lantern bugs (Hemiptera, Auchenorrhyncha, family Fulgoridae) from India and Malaysia was therefore analysed from high-speed videos. The kinematics showed that jumps were propelled by rapid and synchronous movements of both hind legs, with their trochantera moving first. The hind legs were 20-40% longer than the front legs, which was attributable to longer tibiae. It took 5-6 ms to accelerate to take-off velocities reaching 4.65 m s-1 in the best jumps by female Kalidasa lanata. During these jumps, adults experienced an acceleration of 77 g, required an energy expenditure of 4800 µJ and a power output of 900 mW, and exerted a force of 400 mN. The required power output of the thoracic jumping muscles was 21,000 W kg-1, 40 times greater than the maximum active contractile limit of muscle. Such a jumping performance therefore required a power amplification mechanism with energy storage in advance of the movement, as in their smaller relatives. These large lantern bugs are near isometrically scaled-up versions of their smaller relatives, still achieve comparable, if not higher, take-off velocities, and outperform other large jumping insects such as grasshoppers.


Assuntos
Hemípteros , Animais , Fenômenos Biomecânicos , Extremidades , Feminino , Locomoção , Músculo Esquelético
2.
Indian Pediatr ; 56(6): 504-505, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31278233

RESUMO

BACKGROUND: Co-occurrence of amebic hepatitis and Kawasaki disease has not been reported previously. CASE CHARACTERISTICS: We describe two children (aged 4 y and 5 y) with Kawasaki disease and coexisting liver abscess. They were treated with intravenous immunoglobulins with/without percutaneous drainage in combination with amebicidal agents. OUTCOME: Both the children were completely cured of the amebic hepatitis, and had normalization and regression of coronaries at follow-up. MESSAGE: We report the co-existence of amebic hepatitis with Kawasaki disease.


Assuntos
Abscesso Hepático Amebiano/diagnóstico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Pré-Escolar , Feminino , Humanos , Abscesso Hepático Amebiano/complicações , Masculino , Síndrome de Linfonodos Mucocutâneos/complicações
3.
J Clin Diagn Res ; 9(9): PC01-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26500944

RESUMO

BACKGROUND: Breast cancer is often classified into subtypes using immunohistochemical markers. These subtypes have distinct biological behaviour. This study was conducted with the aim of estimating the distribution of various subtypes of breast cancer in Indian population based on immunohistochemistry markers and to determine the clinical features, pathology and outcomes of these subtypes of breast cancer. MATERIALS AND METHODS: A retrospective study was undertaken and all patients of breast cancer over a 5 year period were included. These patients were divided into 4 subgroups depending on the presence or absence of immunohistochemical markers: i) Luminal A (ER/PR+, Her 2 neu-); ii) Luminal B (ER/PR+, Her 2 neu+); iii) Her 2 enriched (ER-/PR-, Her 2 neu+) and; iv) Triple negative (ER-, PR-, Her2 neu-). Clinical and pathological features and survival were compared between patients in the 4 subgroups. RESULTS: Luminal A subgroup had majority of patients (43.8%). Patients in Luminal B, Her 2 enriched, and Triple negative subgroups were 14.8%, 16.1% and 25.3%. Median follow-up of patients was for 34 months. Luminal A subgroup patients were more likely to be postmenopausal and have smaller and lower grade (I/II) tumours with better survival (OS-91.06%). Patients in the Triple negative subgroup were more likely to be premenopausal (p-value 0.036, odds ratio 0.611, CI 0.394-0.949), have larger and higher grade (III) tumours with worse overall survival (OS-88.46%, odds ratio 1.32, 95%CI 0.602-2.39). Her 2 enriched group patients had bad prognostic features like larger size of tumour and higher grade of tumour and worst survival among all the subgroups (OS-85.07%, odds ratio 1.78, 95% CI 0.767-4.163). However, these outcomes were not statistically significant for the subgroups. CONCLUSION: A retrospective study was undertaken of breast cancer patients in India, according to subtypes based on immunohistochemistry. Luminal A had prognostic features and survival which was better as compared to other subgroups (Luminal B, Her 2 enriched and Triple negative). Incidence of patients with Triple negative breast cancer was higher in the premenopausal period. Patients with Her 2 enriched breast cancer had the worst survival among all the subgroups.

4.
Anaesth Intensive Care ; 42(2): 207-12, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24580386

RESUMO

The decision to attempt a percutaneous airway in a recognised 'Can't Intubate, Can't Oxygenate' (CICO) situation may occur too late to avoid a poor outcome. Our study was designed to investigate the effect of high-fidelity simulation on the confidence and decision-making ability of anaesthesia trainees in managing CICO scenarios in subsequent simulation. Nine anaesthesia trainees from Logan Hospital participated. Pre-study questionnaires surveying confidence levels in various anaesthetic crises were completed. All participants underwent an education session based on algorithms developed for failed intubation and ventilation, and techniques for securing percutaneous airway access. However, only four of the nine participated in a high-fidelity simulation session. All nine participants were then filmed during 'mini-simulation' assessment sessions and completed post-study questionnaires identical to those at the commencement of the study. The four trainees who had undertaken the initial high-fidelity simulation had a lower median time to laryngeal mask airway attempt (60 versus 115 seconds) and time to percutaneous airway attempt (111 versus 172 seconds) in the subsequent simulation. The median number of deviations from the Difficult Airway Society algorithm was 0 for the simulation group compared to 1 for the non-simulation group. This small study suggests that high-fidelity simulation shortens the decision-making time of anaesthesia trainees in subsequent simulated CICO scenarios. This observation warrants follow-up in larger prospective trials.


Assuntos
Anestesiologia/educação , Tomada de Decisões , Simulação de Paciente , Humanos , Intubação Intratraqueal
5.
Cell Death Dis ; 5: e1118, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24625977

RESUMO

Mortalin (mot-2) induces inactivation of the tumor suppressor p53's transcriptional and apoptotic functions by cytoplasmic sequestration of p53 in select cancers. The mot-2-dependent cytoprotective function enables cancer cells to support malignant transformation. Abrogating the p53-mot-2 interaction can control or slow down the growth of cancer cells. In this study, we report the discovery of a ubiquitin-like (UBX)-domain-containing protein, UBXN2A, which binds to mot-2 and consequently inhibits the binding between mot-2 and p53. Genetic analysis showed that UBXN2A binds to mot-2's substrate binding domain, and it partly overlaps p53's binding site indicating UBXN2A and p53 likely bind to mot-2 competitively. By binding to mot-2, UBXN2A releases p53 from cytosolic sequestration, rescuing the tumor suppressor functions of p53. Biochemical analysis and functional assays showed that the overexpression of UBXN2A and the functional consequences of unsequestered p53 trigger p53-dependent apoptosis. Cells expressing shRNA against UBXN2A showed the opposite effect of that seen with UBXN2A overexpression. The expression of UBXN2A and its apoptotic effects were not observed in normal colonic epithelial cells and p53-/- colon cancer cells. Finally, significant reduction in tumor volume in a xenograft mouse model in response to UBXN2A expression was verified in vivo. Our results introduce UBXN2A as a home defense response protein, which can reconstitute inactive p53-dependent apoptotic pathways. Inhibition of mot-2-p53 interaction by UBXN2A is an attractive therapeutic strategy in mot-2-elevated tumors.


Assuntos
Apoptose , Neoplasias do Colo/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinas/metabolismo , Animais , Sítios de Ligação , Ligação Competitiva , Caspase 3/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Regulação Neoplásica da Expressão Gênica , Terapia Genética , Células HCT116 , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Células HT29 , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células MCF-7 , Proteínas de Membrana/genética , Camundongos , Proteínas Mitocondriais/genética , Transporte Proteico , Interferência de RNA , Fatores de Tempo , Transfecção , Carga Tumoral , Proteína Supressora de Tumor p53/genética , Ubiquitinas/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Indian J Cancer ; 51(4): 594-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26842207

RESUMO

BACKGROUND: The proportion of breast cancer is rising in India. It presents at a younger age in India as compared to the western countries. AIMS: This is a retrospective study of 86 breast cancer patients less than 40 years treated in a single center from June 2006 to June 2011. The aim was to assess the factors that may influence clinical outcome. MATERIALS AND METHODS: Data were collected from medical records. Variables such as age, stage, surgery, chemotherapy, tumor size, grade, nodal status, perinodal extension, lymphovascular emboli, estrogen receptor, progesterone receptor, and HER-2 neu were analyzed in relation to outcome. RESULTS: Out of total 613 breast cancer patients, 91 (14.8%) were younger than 40 years. Five were excluded due to incomplete data; hence, 86 patients were included in this study. Median tumor size was 3 cm and lymph node positivity was 56.9%. Lymphovascular emboli were positive in 48.8% and perinodal extension was positive in 41.8%. Estrogen receptor positivity was 34.8%, progesterone receptor positivity was 45.3%, and triple negativity was 45.3%. The median follow-up period was 27 months with disease free survival being 73.2% and overall survival being 87.2%. In univariate analysis, the factors significantly associated with survival were stage at presentation, presence of lymphovascular emboli, perinodal extension and grade of the tumor. In multivariate analysis grade of tumor was the only significant factor. CONCLUSIONS: In young women with breast cancer, the factors significantly associated with survival were clinical stage at presentation, the presence of lymphovascular emboli and perinodal extension and grade of tumor.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/terapia , Carcinoma Papilar/patologia , Carcinoma Papilar/terapia , Antraciclinas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Quimioterapia Adjuvante , Feminino , Humanos , Índia , Mastectomia Segmentar , Metotrexato/administração & dosagem , Terapia Neoadjuvante , Estadiamento de Neoplasias , Radioterapia Adjuvante , Estudos Retrospectivos , Tamoxifeno/administração & dosagem , Taxoides/administração & dosagem , Centros de Atenção Terciária , Resultado do Tratamento , Carga Tumoral
7.
Appl Microbiol Biotechnol ; 96(3): 841-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22968354

RESUMO

Enzymatically catalyzed biofuel cells show unique specificity and promise high power densities, but suffer from a limited lifetime due to enzyme deactivation. In the present work, we demonstrate a novel concept to extend the lifetime of a laccase-catalyzed oxygen reduction cathode in which we decouple the electrode lifetime from the limited enzyme lifetime by a regular resupply of fresh enzymes. Thereto, the adsorption behavior of laccase from Trametes versicolor to buckypaper electrode material, as well as its time-dependent deactivation characteristics, has been investigated. Laccase shows a Langmuir-type adsorption to the carbon nanotube-based buckypaper electrodes, with a mean residence time of 2 days per molecule. In a citrate buffer of pH 5, laccase does not show any deactivation at room temperature for 2 days and exhibits a half-life of 9 days. In a long-term experiment, the laccase electrodes were operated at a constant galvanostatic load. The laccase-containing catholyte was periodically exchanged against a freshly prepared one every second day to provide sufficient active enzymes in the catholyte for the replacement of desorbed inactive enzymes. Compared to a corresponding control experiment without catholyte exchange, this procedure resulted in a 2.5 times longer cathode lifetime of 19 ± 9 days in which the electrode showed a potential above 0.744 V vs. normal hydrogen electrode at 110 µA cm(-2). This clearly indicates the successful exchange of molecules by desorption and re-adsorption and is a first step toward the realization of a self-regenerating enzymatic biofuel cell in which enzyme-producing microorganisms are integrated into the electrode to continuously resupply fresh enzymes.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Lacase/metabolismo , Trametes/enzimologia , Eletricidade Estática , Fatores de Tempo
8.
Opt Express ; 20(8): 8915-9, 2012 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-22513602

RESUMO

We present a narrow linewidth continuous laser source with over 11 W output power at 780 nm, based on single-pass frequency doubling of an amplified 1560 nm fibre laser with 36% efficiency. This source offers a combination of high power, simplicity, mode quality and stability. Without any active stabilization, the linewidth is measured to be below 10 kHz. The fibre seed is tunable over 60 GHz, which allows access to the D2 transitions in 87Rb and 85Rb, providing a viable high-power source for laser cooling as well as for large-momentum-transfer beamsplitters in atom interferometry. Sources of this type will pave the way for a new generation of high flux, high duty-cycle degenerate quantum gas experiments.

9.
J Postgrad Med ; 56(4): 275-80, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20935398

RESUMO

BACKGROUND: Scorpion venoms cause a massive release of neurotransmitters. Either anti-scorpion venom serum (AScVS) or prazosin has been used in the management of severe scorpion envenomation. AIMS: To compare the time taken for clinical recovery by patients with severe scorpion envenomation after AScVS therapy with that following prazosin therapy. SETTINGS AND DESIGN: A prospective, open-labeled clinical trial was undertaken to compare the effects of the AScVS and/or prazosin on clinical recovery in scorpion-stung patients. MATERIALS AND METHODS: Eighty-one patients from rural districts of Maharashtra presenting with severe scorpion envenomation were assigned to three treatment groups (AScVS: n = 28; prazosin: n = 25; AScVS + prazosin: n = 28). Severity of scorpion envenomation was graded using a proposed composite clinical scoring system to assess the therapeutic efficacy. AScVS was administered as an intravenous slow bolus, ranging from 40 to 100 ml, depending on the severity of envenomation. Prazosin was given as 1 mg every 3 h. STATISTICAL ANALYSIS USED: The non-parametric "Kruskal-Wallis" test was used in the statistical analysis and a P-value of 0.05 was considered significant. RESULTS: Mean composite scores of patients from the three groups at the time of admission were comparable. Complete clinical recovery was noted in 4.14 ± 1.6 h and 19.28 ± 5.03 h in the subjects who were administered AScVS and prazosin, respectively (P < 0.001). There was no incidence of anaphylactic reaction to AScVS. CONCLUSIONS: Intravenous slow bolus of AScVS given based on the clinical severity of envenomation leads to early recovery than prazosin alone and is well tolerated.


Assuntos
Antivenenos/uso terapêutico , Prazosina/uso terapêutico , Picadas de Escorpião/tratamento farmacológico , Venenos de Escorpião/uso terapêutico , Escorpiões , Adolescente , Adulto , Idoso , Animais , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , População Rural , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
10.
Sex Dev ; 3(5): 245-52, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19940443

RESUMO

Turner Syndrome (TS) is a disorder of human females associated with complete or partial loss of one of the X chromosomes, varying degrees of multiple congenital malformations and gonadal dysgenesis. However, the reason for the premature loss of germ cells in the TS ovaries is currently unknown. To understand the molecular basis of the gonadal dysgenesis the mRNA expression of Mullerian Inhibiting Substance (MIS) was examined in human fetal and adult TS ovaries and compared with normal ovaries by in situ hybridization. The expression of MIS was found to be increased in the granulosa cells of the TS ovaries as compared to that in normal ovaries, and these granulosa cells were organized to form testicular tubule like structures. MIS was also found to be ectopically expressed in the oocytes of the developing TS gonads. The stromal cells of the streak gonads of adult TS women abundantly expressed MIS. We speculate that the absence of a second X chromosome leads to over-expression of MIS that may be co-responsible for failure of ovarian differentiation in TS. MIS may be a potential negative regulator of ovarian development in humans.


Assuntos
Hormônio Antimülleriano/metabolismo , Regulação da Expressão Gênica , Ovário/metabolismo , Síndrome de Turner/genética , Síndrome de Turner/metabolismo , Adulto , Hormônio Antimülleriano/genética , Feminino , Disgenesia Gonadal/genética , Gônadas/metabolismo , Células da Granulosa/metabolismo , Humanos , Hibridização in Situ Fluorescente , Oócitos/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Processos de Determinação Sexual
11.
Indian J Med Res ; 130(1): 63-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19700803

RESUMO

BACKGROUND & OBJECTIVE: Enteric parasites are major cause of diarrhoea in HIV infected individuals. The present study was undertaken to detect enteric parasites in HIV infected patients with diarrhoea at different levels of immunity. METHODS: The study was carried out at National AIDS Research Institute, Pune, India, between March 2002 and March 2007 among consecutively enrolled 137 HIV infected patients presenting with diarrhoea. Stool samples were collected and examined for enteric parasites by microscopy and special staining methods. CD4 cell counts were estimated using the FACS count system. RESULTS: Intestinal parasitic pathogens were detected in 35 per cent patients, and the major pathogens included Cryptosporidium parvum (12%) the most common followed by Isospora belli (8%), Entamoeba histolytica/Enatmoeba dispar (7%), Microsporidia (1%) and Cyclospora (0.7%). In HIV infected patients with CD4 count < 200 cells/microl, C. parvum was the most commonly observed (54%) pathogen. Proportion of opportunistic pathogens in patients with CD4 count <200 cells/microl was significantly higher as compared with other two groups of patients with CD4 count >200-499 and >or= 500 cells/microl (P=0.001, P=0.016) respectively. INTERPRETATION & CONCLUSION: Parasitic infections were detected in 35 per cent HIV infected patients and low CD4 count was significantly associated with opportunistic infection. Detection of aetiologic pathogens might help clinicians decide appropriate management strategies.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Diarreia/etiologia , Infecções por HIV , Terapia de Imunossupressão , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Infecções Oportunistas Relacionadas com a AIDS/fisiopatologia , Adulto , Feminino , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/parasitologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Intern Emerg Med ; 2(4): 302-10, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18060470

RESUMO

OBJECTIVE: To determine the feasibility of using the internet to track the spread of emergency medicine internationally. OVERVIEW: This was an attempt to perform a descriptive cross-sectional study employing a web-based survey. SUBJECTS: Potential respondents were identified from multiple sources. OBSERVATIONS: The primary outcome was the response to 16 questions about EM care and the setting in which it was delivered for acute cardiac, paediatric, obstetrical illnesses and trauma. The questions were divided into six general areas and elicited for urban, semi-urban and rural settings. A series of four e-mails soliciting completion of the survey were sent to potential respondents. ANALYSIS: Simple descriptive statistics. RESULTS: We identified 358 potential respondents with valid e-mail addresses over a period of three years. Overall, 145 (41%) responded and 117 (33% 95% CI 28-38%) of them were complete and interpretable. There was one response from 54 and two responses from 29 countries, representing an overall response rate by country surveyed of 65% (95% CI 57-73%), but of all existing countries of only 43% (95% CI 36-50%). Based on sparse data, it appears that in urban areas, 47% (obstetrics) to 65% (paediatric) of acutely sick or injured patients are taken to an ED-equivalent. For rural areas, this range was 19% (obstetrical) to 40% (trauma). CT scans are available in 78% of urban ED-equivalents but 12% of rural ones. Haematocrits are available in 72% of rural settings. In 60% of responding nations, some type of EM training was available, and in 42% physicians went abroad to study EM. CONCLUSIONS: A survey of international EM is challenging to achieve because of difficulty in both identifying and in contacting potential respondents. Based on sparse data, population density (urban, rural) appears to be related to both the location to which acutely ill patients are taken for their care and to the level of technology available. The specialty of EM is now recognised internationally and education in EM is common.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Cooperação Internacional , Estudos Transversais , Planejamento em Desastres , Serviço Hospitalar de Emergência/tendências , Pesquisas sobre Atenção à Saúde , Acessibilidade aos Serviços de Saúde/tendências , Humanos , Projetos Piloto , Inquéritos e Questionários , Fatores de Tempo
14.
Appl Radiat Isot ; 59(2-3): 145-50, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12941504

RESUMO

Two procedures for fixing the 125I activity on different matrices were explored. In the first method, anodic deposition of 125I on silver wire was used. In the second, 125I was adsorbed as iodate (IO3-) on alumina microspheres by using a solid-solution interface technique. While the 125I uptake was approximately 84% on the silver wires by electrodeposition method, the microspheres showed approximately 97% by the solid-solution interface technique. The low leachable (0.05%) wires, and comparatively high leachable (approximately 4%) spheres were trial encapsulated and laser welded. The encapsulated sources were measured for source strength and were found to be suitable for the treatment of eye cancer.


Assuntos
Braquiterapia/instrumentação , Braquiterapia/métodos , Materiais Revestidos Biocompatíveis/síntese química , Neoplasias Oculares/radioterapia , Radioisótopos do Iodo/uso terapêutico , Adsorção , Galvanoplastia/métodos , Humanos , Radioisótopos do Iodo/química , Teste de Materiais , Microesferas , Doses de Radiação , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/uso terapêutico
15.
Mol Hum Reprod ; 9(4): 219-25, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12651904

RESUMO

The purpose of the study was to examine the occurrence of programmed cell death (apoptosis) in normal and chromosomally aneuploid testis and ovaries during the second trimester of human development. Such information may be useful in understanding normal and abnormal germ cell development and disorders associated with infertility in adult life. Apoptosis was studied by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) analysis in human fetal ovaries (n = 16) and testis (n = 14) between 9 and 23 weeks of development, in ovaries of four Turner's syndrome fetuses (45X) and in the gonad of an XO/XY fetus. In normal fetal testis, a small proportion of germ cells, Sertoli cells and Leydig cells undergo apoptosis. In normal fetal ovaries, some developing oocytes and granulosa cells were detected as TUNEL positive. Semiquantitative analysis of fetal ovaries revealed that approximately 3-7% of oocytes were apoptotic. In abnormal fetal testis (XO/XY genotype). TUNEL analysis revealed that only germ cells not enclosed in seminiferous tubules undergo apoptosis. TUNEL analysis of the Turner's syndrome (45X) ovaries studied at 15 and 20 weeks of development revealed massive apoptosis of the oocytes. Nearly 50-70% of the oocytes were TUNEL positive in these ovaries. These results suggest that germ cell apoptosis is a common event occurring during development of human gonads. Chromosomal defects by some means accelerates apoptosis that probably leads to gonadal dysgenesis later in life.


Assuntos
Aneuploidia , Apoptose/fisiologia , Células Germinativas/fisiologia , Ovário/embriologia , Aberrações dos Cromossomos Sexuais , Testículo/embriologia , Feminino , Feto/fisiologia , Humanos , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Masculino , Ovário/citologia , Ovário/fisiologia , Fosfoproteínas/metabolismo , Gravidez , Segundo Trimestre da Gravidez , Testículo/citologia , Testículo/fisiologia
16.
J Exp Biol ; 204(Pt 15): 2607-26, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11533111

RESUMO

We used a dynamically scaled mechanical model of the fruit fly Drosophila melanogaster to study how changes in wing kinematics influence the production of unsteady aerodynamic forces in insect flight. We examined 191 separate sets of kinematic patterns that differed with respect to stroke amplitude, angle of attack, flip timing, flip duration and the shape and magnitude of stroke deviation. Instantaneous aerodynamic forces were measured using a two-dimensional force sensor mounted at the base of the wing. The influence of unsteady rotational effects was assessed by comparing the time course of measured forces with that of corresponding translational quasi-steady estimates. For each pattern, we also calculated mean stroke-averaged values of the force coefficients and an estimate of profile power. The results of this analysis may be divided into four main points. (i) For a short, symmetrical wing flip, mean lift was optimized by a stroke amplitude of 180 degrees and an angle of attack of 50 degrees. At all stroke amplitudes, mean drag increased monotonically with increasing angle of attack. Translational quasi-steady predictions better matched the measured values at high stroke amplitude than at low stroke amplitude. This discrepancy was due to the increasing importance of rotational mechanisms in kinematic patterns with low stroke amplitude. (ii) For a 180 degrees stroke amplitude and a 45 degrees angle of attack, lift was maximized by short-duration flips occurring just slightly in advance of stroke reversal. Symmetrical rotations produced similarly high performance. Wing rotation that occurred after stroke reversal, however, produced very low mean lift. (iii) The production of aerodynamic forces was sensitive to changes in the magnitude of the wing's deviation from the mean stroke plane (stroke deviation) as well as to the actual shape of the wing tip trajectory. However, in all examples, stroke deviation lowered aerodynamic performance relative to the no deviation case. This attenuation was due, in part, to a trade-off between lift and a radially directed component of total aerodynamic force. Thus, while we found no evidence that stroke deviation can augment lift, it nevertheless may be used to modulate forces on the two wings. Thus, insects might use such changes in wing kinematics during steering maneuvers to generate appropriate force moments. (iv) While quasi-steady estimates failed to capture the time course of measured lift for nearly all kinematic patterns, they did predict with reasonable accuracy stroke-averaged values for the mean lift coefficient. However, quasi-steady estimates grossly underestimated the magnitude of the mean drag coefficient under all conditions. This discrepancy was due to the contribution of rotational effects that steady-state estimates do not capture. This result suggests that many prior estimates of mechanical power based on wing kinematics may have been grossly underestimated.


Assuntos
Drosophila melanogaster/fisiologia , Voo Animal , Asas de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Matemática
17.
Indian J Pediatr ; 68(2): 173-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11284187

RESUMO

An extremely rare case of long, thin and sharp pin in a young boy which was inhaled initially and defied removal at branchoscopy was eventually recovered in stool after a long and variable course through alimentary tract has been reported.


Assuntos
Brônquios , Sistema Digestório , Corpos Estranhos , Traqueia , Criança , Tosse , Defecação , Corpos Estranhos/diagnóstico por imagem , Humanos , Masculino , Radiografia
18.
Am J Trop Med Hyg ; 62(3): 402-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11037786

RESUMO

In India, treatment of acute, uncomplicated Plasmodium falciparum malaria is becoming increasingly difficult due to resistance to chloroquine, thus there is a need for new antimalarial drugs. CGP 56697 (co-artemether), a new drug, is a combination of artemether and lumefantrine in a single oral formulation (one tablet = 20 mg of artemether plus 120 mg of lumefantrine). In a double-blind study, 179 patients with acute uncomplicated P. falciparum malaria were randomly assigned to receive either CGP (n = 89) given as a short course of 4 x 4 tablets over a 48-hr period or chloroquine (n = 90) given as four tablets (one tablet = 150 mg of chloroquine base) initially, followed by two tablets each at 6-8, 24, and 48 hr. Due to a death in the chloroquine group and a decrease in the chloroquine cure rate to < 50% (based on the blinded overall cure rate at that time), recruitment was terminated prematurely. CGP 56697 showed a superior 28-day cure rate (95.4% versus 19.7%; P < 0.001), time to parasite clearance (median = 36 versus 60 hr; P < 0.001), and resolution of fever (median = 18 versus 27 hr; P = 0.0456). This drug provides a safe, effective, and rapid therapy for the treatment of acute uncomplicated P. falciparum malaria.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas , Cloroquina/uso terapêutico , Fluorenos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Doença Aguda , Administração Oral , Adolescente , Adulto , Idoso , Combinação Arteméter e Lumefantrina , Cloroquina/administração & dosagem , Cloroquina/efeitos adversos , Método Duplo-Cego , Combinação de Medicamentos , Eletrocardiografia , Etanolaminas , Feminino , Fluorenos/administração & dosagem , Fluorenos/efeitos adversos , Humanos , Malária Falciparum/fisiopatologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sesquiterpenos/administração & dosagem , Sesquiterpenos/efeitos adversos , Fatores de Tempo
19.
Anal Biochem ; 285(1): 33-49, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10998261

RESUMO

We present an improved technique for estimating protein secondary structure content from amide I and amide III band infrared spectra. This technique combines the superposition of reference spectra of pure secondary structure elements with simultaneous aromatic side chain, water vapor, and solvent background subtraction. Previous attempts to generate structural reference spectra from a basis set of reference protein spectra have had limited success because of inaccuracies arising from sequential background subtractions and spectral normalization, arbitrary spectral band truncation, and attempted resolution of spectroscopically degenerate structure classes. We eliminated these inaccuracies by defining a single mathematical function for protein spectra, permitting all subtractions, normalizations, and amide band deconvolution steps to be performed simultaneously using a single optimization algorithm. This approach circumvents many of the problems associated with the sequential nature of previous methods, especially with regard to removing the subjectivity involved in each processing step. A key element of this technique was the calculation of reference spectra for ordered helix, unordered helix, sheet, turns, and unordered structures from a basis set of spectra of well-characterized proteins. Structural reference spectra were generated in the amide I and amide III bands, both of which have been shown to be sensitive to protein secondary structure content. We accurately account for overlaps between amide and nonamide regions and allow different structure types to have different extinction coefficients. The agreement between our structure estimates, for proteins both inside and outside the basis set, and the corresponding determinations from X-ray crystallography is good.


Assuntos
Estrutura Secundária de Proteína , Animais , Humanos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Água
20.
J Surg Res ; 93(1): 21-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10945939

RESUMO

BACKGROUND: Recently, eicosapentaenoic acid (EPA) was found to have an anti-inflammatory effect attributable to diminished synthesis of arachidonic acid metabolites that initiate acute lung injury. We evaluated the ability of dietary EPA supplementation to prevent endotoxin-induced acute lung injury in rats. MATERIALS AND METHODS: Rats fed a standard diet were divided randomly into two groups: for 2 weeks one group additionally was fed 1000 mg/kg/day of EPA ethyl ester emulsion (EPA rats), while in the other group the diet was supplemented with vehicle alone (control rats). Fatty acid components of alveolar macrophages (AM) were measured, as well as leukotriene (LT) B(4) and LTB(5) production by AM exposed in vitro to calcium ionophore A23187. Plasma concentrations of thromboxane (Tx) B(2), a stable metabolite of TxA(2), were examined 1 h after inducing lung injury with endotoxin (2 mg/kg iv). At 6 h, wet/dry (W/D) weight ratios were calculated for the lungs to assess pulmonary edema, and neutrophils were counted in pulmonary parenchyma and peripheral blood. RESULTS: Arachidonic acid content and LTB(4) generation in AM were significantly lower in EPA rats than in controls; conversely, EPA content and LTB(5) generation in AM were significantly higher in the EPA group. Neutrophil counts in lung parenchyma and peripheral blood did not differ between groups, but W/D and plasma TxB(2) concentrations were significantly lower in EPA rats. CONCLUSIONS: EPA supplementation depressed arachidonic acid content and LTB(4) generation in AM and plasma TxB(2) in our model, leading to decreased pulmonary edema.


Assuntos
Ácido Eicosapentaenoico/uso terapêutico , Edema Pulmonar/prevenção & controle , Animais , Ácido Araquidônico/metabolismo , Endotoxemia/complicações , Ácidos Graxos/biossíntese , Leucotrieno B4/biossíntese , Masculino , Neutrófilos/fisiologia , Ratos , Ratos Wistar , Síndrome do Desconforto Respiratório/prevenção & controle , Tromboxano B2/sangue
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