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1.
Indian J Otolaryngol Head Neck Surg ; 76(2): 1765-1769, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566634

RESUMO

Good glottic exposure is a prerequisite for a good microlaryngeal surgery. Often this is difficult to predict preoperatively. This study aims to evaluate the utility of office-based rigid laryngoscopy (70°) as a screening tool to predict laryngeal exposure during micro laryngoscopy. Sixty-nine patients underwent office-based rigid laryngeal examination followed by micro laryngoscopic surgery for benign vocal cord lesions. Office-based laryngoscopy was classified as grade 1 when the entire glottis with anterior commissure (AC) was visualized without undue traction of tongue; grade 2 when AC was visualized only during phonation and with some traction of tongue and grade 3 when there is an inability to visualise the glottis adequately despite moderate traction of tongue and the examination was completed using a flexible scope. These were correlated with laryngeal exposure during micro laryngoscopy. 42 patients were categorized as grade 1 out of which 39 (93%) had a favourable laryngeal exposure (class 1) while only 3 (7%) had a partially favourable exposure (class 2). 18 patients were categorized as grade 2 out of which 12(66%) had a favourable exposure (class 1) as against 6 (33%) who had a partially favourable exposure (class 2). Nine of our patients were categorized as grade 3 out of which all 9 (100%) had an unfavourable exposure (class 3) requiring angled tele laryngoscopy to complete the surgery. A strong correlation between office-based laryngoscopic grading and exposure during operative laryngoscopy was obtained statistically (Cramer's V test, V = 0.746). Office examination with a 70° telescope is a good predictor of glottic exposure during micro laryngoscopy. We believe that the ease of performing a micro laryngoscopy in the operating room is directly proportional to the ease of doing laryngoscopy in the office.

2.
Indian J Otolaryngol Head Neck Surg ; 75(3): 2217-2221, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37636757

RESUMO

Idiopathic ulcerative laryngitis (IUL) is characterized by bilateral ulceration of vocal cords which is followed by a protracted course of healing. It is rarely diagnosed, with a paucity of published data in English literature. There is no published data on this topic in the Indian population. Twenty-one patients from 3 centres were prospectively evaluated for clinical presentation, diagnosis, treatment, and follow-up. All patients underwent fibreoptic laryngoscopic evaluation and stroboscopic assessment. They were treated with supportive care and stringent follow-up. 21 patients with a median age of 39 years were included. This condition was commonly seen in males. All patients were treated conservatively except two who underwent a biopsy. The average time for full recovery in 14 of our patients who had compliant follow-ups was 9.24 weeks. GRBAS score improved from 9 to 5.93(p < 0.0001). Self-reported voice outcomes improved in all patients except for one patient who had a biopsy. IUL is uncommon but not rare in the Indian population. It shows full recovery with conservative management that involves at least more than 3-4 weeks.

3.
Sci Rep ; 9(1): 14827, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597936

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

4.
Sci Rep ; 9(1): 5584, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944383

RESUMO

Stomata are adjustable pores in the aerial epidermis of plants. The role of stomata is usually described in terms of the trade-off between CO2 uptake and water loss. Little consideration has been given to their interaction with below-ground development or diffusion of other gases. We overexpressed the rice EPIDERMAL PATTERNING FACTOR1 (OsEPF1) to produce rice plants with reduced stomatal densities, resulting in lowered leaf stomatal conductance and enhanced water use efficiency. Surprisingly, we found that root cortical aerenchyma (RCA) is formed constitutively in OsEPF1OE lines regardless of tissue age and position. Aerenchyma is tissue containing air-spaces that can develop in the plant root during stressful conditions, e.g. oxygen deficiency when it functions to increase O2 diffusion from shoot to root. The relationship with stomata is unknown. We conclude that RCA development and stomatal development are linked by two possible mechanisms: first that reduced stomatal conductance inhibits the diffusion of oxygen to the root, creating an oxygen deficit and stimulating the formation of RCA, second that an unknown EPF signalling pathway may be involved. Our observations have fundamental implications for the understanding of whole plant gas diffusion and root-to-shoot signalling events.

5.
Zootaxa ; 4462(2): 251-256, 2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30314046

RESUMO

A new species of snake eel (Anguilliformes: Ophichthidae: Ophichthinae), Ophichthus johnmccoskeri sp. nov., is described from three specimens collected from the northern part of the Bay of Bengal, India. Ophichthus johnmccoskeri sp. nov. is distinguished from its congeners by having the dorsal-fin origin well behind the pectoral-fin tips, by tooth pattern (lower jaw with a single row anteriorly followed by biserial teeth on anterior sides and tri-serial teeth posteriorly), and vertebral count (24 predorsal, 51-52 preanal, and 156-158 total).The new species has a single barbel between the anterior and posterior nostrils; vomerine teeth biserial anteriorly, multi to triserial and biserial medially and in a single row posteriorly; maxillary teeth biserial anteriorly and triserial posteriorly; tip of the lower jaw toothless; and tail length 1.6 times in total length.


Assuntos
Distribuição Animal , Enguias , Animais , Baías , Índia
6.
J Clin Diagn Res ; 11(7): MD09-MD10, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28892945

RESUMO

Nevus sebaceus of Jadassohn is a congenital tumour affecting the scalp and face. It is usually presented as a pigmented patch or plaque. It is a complex cutaneous hamartoma which involves pilosebaceous follicle, epidermis and adnexal structures. Tumours that arise from nevus sebaceous are basal cell carcinoma, syringocystadenoma papilliferum, trichoblastoma and hidradenoma. The progression and frequency of the tumour increase with the age. Here we present a case of pigmented trichoblastoma over the external nose. It was a case of an elderly woman presenting with a painless swelling over the external nose which was soft, non-tender and with well defined margins.

7.
Dev Biol ; 425(1): 1-7, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28263767

RESUMO

The number of root cortex cell layers varies among plants, and many species have several cortical cell layers. We recently demonstrated that the two rice orthologs of the Arabidopsis SHR gene, OsSHR1 and OsSHR2, could complement the A. thaliana shr mutant. Moreover, OsSHR1 and OsSHR2 expression in A. thaliana roots induced the formation of extra root cortical cell layers. In this article, we demonstrate that the overexpression of AtSHR and OsSHR2 in rice roots leads to plants with wide and short roots that contain a high number of extra cortical cell layers. We hypothesize that SHR genes share a conserved function in the control of cortical cell layer division and the number of ground tissue cell layers in land plants.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Raízes de Plantas/genética , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Divisão Celular/genética , Teste de Complementação Genética , Microscopia Confocal , Mutação , Oryza/citologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
J Oral Maxillofac Pathol ; 18(1): 149, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24959060

RESUMO

Lipomas in the submandibular space are uncommon. This report describes a case of lipoma in the submandibular space. The clinical features, imaging study, histopathological features and management of the tumor are described.

9.
Biotechnol Genet Eng Rev ; 30(1-2): 95-112, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25652818

RESUMO

A better understanding of the development and architecture of roots is essential to develop strategies to increase crop yield and optimize agricultural land use. Roots control nutrient and water uptake, provide anchoring and mechanical support and can serve as important storage organs. Root growth and development is under tight genetic control and modulated by developmental cues including plant hormones and the environment. This review focuses on root architecture and its diversity and the role of environment, nutrient, and water as well as plant hormones and their interactions in shaping root architecture.


Assuntos
Ecossistema , Regulação da Expressão Gênica de Plantas/fisiologia , Homeostase/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/fisiologia
10.
Indian J Otolaryngol Head Neck Surg ; 64(3): 230-2, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23998025

RESUMO

Tympanoplasty has been the mainstay of treatment in chronic otitis media. In a non cholesteatomatous chronic otitis media, there has been much debate whether a cortical mastoidectomy is required or not. Creating an aerating mastoidectomy in cases of blocked aditus ad antrum helps in reducing the recurrence. However, the status of aditus is not always known unless a mastoidectomy is performed. In this study we try to find out if there is any clinical clue regarding a blocked aditus ad antrum by looking at the tympanic membrane. Fourty-three cases of cortical mastoidectomies were retrospectively studied in this series. Patency of aditus ad antrum was analyzed with respect to presence of myringosclerosis and the status of middle ear mucosa. In this study myringosclerosis was found to be significantly associated with a blocked aditus while no such association was found with the status of middle ear mucosa. The presence of myringosclerosis may indicate a blocked aditus ad antrum and performing a cortical mastoidectomy in such cases may help in creating an aerated mastoid, thereby possibly reducing the recurrence rate.

11.
Plant Cell ; 22(6): 1749-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20562234

RESUMO

Auxin is an essential phytohormone that regulates many aspects of plant development. To identify new genes that function in auxin signaling, we performed a genetic screen for Arabidopsis thaliana mutants with an alteration in the expression of the auxin-responsive reporter DR5rev:GFP (for green fluorescent protein). One of the mutants recovered in this screen, called weak auxin response1 (wxr1), has a defect in auxin response and exhibits a variety of auxin-related growth defects in the root. Polar auxin transport is reduced in wxr1 seedlings, resulting in auxin accumulation in the hypocotyl and cotyledons and a reduction in auxin levels in the root apex. In addition, the levels of the PIN auxin transport proteins are reduced in the wxr1 root. We also show that WXR1 is ROOT UV-B SENSITIVE2 (RUS2), a member of the broadly conserved DUF647 domain protein family found in diverse eukaryotic organisms. Our data indicate that RUS2/WXR1 is required for auxin transport and to maintain the normal levels of PIN proteins in the root.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Dados de Sequência Molecular , Mutação , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , RNA de Plantas/genética , Plântula/crescimento & desenvolvimento
12.
Science ; 312(5777): 1218-20, 2006 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16690816

RESUMO

The AUX1 and PIN auxin influx and efflux facilitators are key regulators of root growth and development. For root gravitropism to occur, AUX1 and PIN2 must transport auxin via the lateral root cap to elongating epidermal cells. Genetic studies suggest that AXR4 functions in the same pathway as AUX1. Here we show that AXR4 is a previously unidentified accessory protein of the endoplasmic reticulum (ER) that regulates localization of AUX1 but not of PIN proteins. Loss of AXR4 resulted in abnormal accumulation of AUX1 in the ER of epidermal cells, indicating that the axr4 agravitropic phenotype is caused by defective AUX1 trafficking in the root epidermis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Raízes de Plantas/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/química , Transporte Biológico , Proteínas de Transporte/química , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Gravitropismo , Herbicidas/farmacologia , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Dados de Sequência Molecular , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Epiderme Vegetal/citologia , Epiderme Vegetal/metabolismo , Coifa/citologia , Coifa/metabolismo , Plantas Geneticamente Modificadas , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo
13.
Plant J ; 28(1): 27-39, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11696184

RESUMO

We report here the molecular characterisation of the Arabidopsis MALE STERILITY1 gene, which is a critical sporophytic controlling factor for anther and pollen development. Homozygous ms1 mutants do not produce viable pollen, but are otherwise phenotypically normal. Degeneration of pollen occurs soon after microspore release from the tetrads, at which time the tapetum also appears abnormally vacuolated. The MS1 gene is expressed at low levels in anthers from closed buds, with expression in the tapetum at the stage of microspore release. No expression is seen in open flowers. The deduced MS1 protein sequence shows strong homology to the PHD-finger motif found in known transcription factors from humans, yeast and higher plants. Six alleles of ms1 have been identified; all result in premature termination of the MS1 protein and loss of the PHD-finger motif. MS1 is likely to play a key role in regulating transcription during specific stages of male gametogenesis and anther development. As such, MS1 provides a valuable tool for the manipulation of male sterility in higher plants.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Gametogênese/genética , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Sequência de Bases , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Dados de Sequência Molecular , Mutação , Fenótipo , Mapeamento Físico do Cromossomo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Genes Dev ; 15(20): 2648-53, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11641271

RESUMO

Auxins represent an important class of plant hormone that regulate plant development. Plants use specialized carrier proteins to transport the auxin indole-3-acetic acid (IAA) to target tissues. To date, efflux carrier-mediated polar auxin transport has been assumed to represent the sole mode of long distance IAA movement. Localization of the auxin permease AUX1 in the Arabidopsis root apex has revealed a novel phloem-based IAA transport pathway. AUX1, asymmetrically localized to the plasma membrane of root protophloem cells, is proposed to promote the acropetal, post-phloem movement of auxin to the root apex. MS analysis shows that IAA accumulation in aux1 mutant root apices is impaired, consistent with an AUX1 phloem unloading function. AUX1 localization to columella and lateral root cap tissues of the Arabidopsis root apex reveals that the auxin permease regulates a second IAA transport pathway. Expression studies using an auxin-regulated reporter suggest that AUX1 is necessary for root gravitropism by facilitating basipetal auxin transport to distal elongation zone tissues.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/metabolismo , Proteínas de Membrana Transportadoras , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Transporte Biológico , Células Cultivadas/citologia , Epitopos , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana/metabolismo , Raízes de Plantas/citologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Transdução de Sinais , Frações Subcelulares
15.
Plant Cell ; 13(4): 843-52, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283340

RESUMO

Lateral root development in Arabidopsis provides a model for the study of hormonal signals that regulate postembryonic organogenesis in higher plants. Lateral roots originate from pairs of pericycle cells, in several cell files positioned opposite the xylem pole, that initiate a series of asymmetric, transverse divisions. The auxin transport inhibitor N-1-naphthylphthalamic acid (NPA) arrests lateral root development by blocking the first transverse division(s). We investigated the basis of NPA action by using a cell-specific reporter to demonstrate that xylem pole pericycle cells retain their identity in the presence of the auxin transport inhibitor. However, NPA causes indoleacetic acid (IAA) to accumulate in the root apex while reducing levels in basal tissues critical for lateral root initiation. This pattern of IAA redistribution is consistent with NPA blocking basipetal IAA movement from the root tip. Characterization of lateral root development in the shoot meristemless1 mutant demonstrates that root basipetal and leaf acropetal auxin transport activities are required during the initiation and emergence phases, respectively, of lateral root development.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Transporte Biológico , Diferenciação Celular , Divisão Celular , Polaridade Celular , Ácidos Indolacéticos/antagonistas & inibidores , Ácidos Indolacéticos/fisiologia , Meristema/anatomia & histologia , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Ftalimidas/farmacologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Transdução de Sinais
16.
Plant J ; 25(4): 399-406, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11260496

RESUMO

The hormone auxin is transported in plants through the combined actions of diffusion and specific auxin influx and efflux carriers. In contrast to auxin efflux, for which there are well documented inhibitors, understanding the developmental roles of carrier-mediated auxin influx has been hampered by the absence of specific competitive inhibitors. However, several molecules that inhibit auxin influx in cultured cells have been described recently. The physiological effects of two of these novel influx carrier inhibitors, 1-naphthoxyacetic acid (1-NOA) and 3-chloro-4-hydroxyphenylacetic acid (CHPAA), have been investigated in intact seedlings and tissue segments using classical and new auxin transport bioassays. Both molecules do disrupt root gravitropism, which is a developmental process requiring rapid auxin redistribution. Furthermore, the auxin-insensitive and agravitropic root-growth characteristics of aux1 plants were phenocopied by 1-NOA and CHPAA. Similarly, the agravitropic phenotype of inhibitor-treated seedlings was rescued by the auxin 1-naphthaleneacetic acid, but not by 2,4-dichlorophenoxyacetic acid, again resembling the relative abilities of these two auxins to rescue the phenotype of aux1. Further investigations have shown that none of these compounds block polar auxin transport, and that CHPAA exhibits some auxin-like activity at high concentrations. Whilst results indicate that 1-NOA and CHPAA represent useful tools for physiological studies addressing the role of auxin influx in planta, 1-NOA is likely to prove the more useful of the two compounds.


Assuntos
Proteínas de Arabidopsis , Glicolatos/farmacologia , Ácidos Indolacéticos/antagonistas & inibidores , Mutação , Fenilacetatos/farmacologia , Proteínas de Plantas/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Transporte Biológico , Gravitropismo , Ácidos Indolacéticos/metabolismo , Fenótipo , Raízes de Plantas/crescimento & desenvolvimento
17.
Biochem Soc Trans ; 28(4): 481-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10961944

RESUMO

Auxins are key regulators of plant development. Plants employ a specialized delivery system termed polar auxin transport to convey indole-3-acetic acid from source to target tissues. Auxin transport is mediated by the combined activities of specialized influx and efflux carriers. Mutational approaches in the model plant, Arabidopsis thaliana, have led to the molecular genetic characterization of putative auxin influx and efflux carrier components, AUX1 and AtPIN1. Both genes belong to distinct gene families that are being functionally characterized by using a reverse genetic approach in Arabidopsis. AtPIN proteins are asymmetrically localized within plant plasma membranes, providing a molecular mechanism for the characteristic polarity of auxin transport. We outline the epitope tagging strategy being used in our laboratory to immunolocalize AUX1 and discuss the implications of its subcellular localization for auxin redistribution within root apical tissues. Lastly, we describe a novel carrier-based mechanism that plant cells might use to determine their relative position(s) within an auxin gradient, drawing parallels with the mechanism of glucose perception in yeast.


Assuntos
Proteínas de Arabidopsis , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras , Fenômenos Fisiológicos Vegetais , Arabidopsis/genética , Transporte Biológico , Membrana Celular/metabolismo , Glucose/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Mutagênese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais , Leveduras/metabolismo
18.
Philos Trans R Soc Lond B Biol Sci ; 353(1374): 1511-5, 1998 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-9800211

RESUMO

Auxin represents one of the most important classes of signalling molecules described in plants. Auxins regulate several fundamental cellular processes including division, elongation and differentiation. Indole-3-acetic acid (IAA), the principal form of auxin in higher plants, is first synthesized within young apical tissues, then conveyed to its basal target tissues by a specialized delivery system termed polar auxin transport. The polarity of IAA movement represents one of the most novel aspect of auxin signalling. IAA transport has been demonstrated to involve auxin influx and efflux carrier activities. The adoption of a mutational approach in the model plant Arabidopsis thaliana has led to the identification of a number of genes which encode components for, or regulate the activity of, the auxin transport machinery. This paper will review the advances being made in identifying and characterizing these auxin transport-related gene products and discuss their importance within the context of Arabidopsis development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Transporte Biológico Ativo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais
19.
Stroke ; 29(9): 1791-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9731596

RESUMO

BACKGROUND AND PURPOSE: Secondary brain injury and edema formation contribute significantly to morbidity and mortality after intracerebral hemorrhage (ICH). The pathogenesis of this process is poorly understood. We sought to characterize alterations in perilesional blood flow that occur during the acute phase of ICH and to determine whether progressive enlargement of edema surrounding ICH is related to increased or decreased perfusion. METHODS: We performed paired consecutive CT and 99mTc-hexamethylpropylenamine oxime single-photon emission computed tomography (SPECT) scans during the acute (mean, 18 hours) and subacute (mean, 72 hours) phase of ICH in 23 patients. Hematoma and edema volumes were traced and calculated from CT images. SPECT-derived hypothetical flow deficit volumes (FDV) around each hematoma were calculated by measuring a "zero-flow" volume within a large perilesional region of interest (based on percent tracer count loss compared with the contralateral side) and subtracting the corresponding ICH volume. Patients with significant midline shift (>5 mm) or global blood flow reduction were excluded from the analysis. RESULTS: ICH volume (18 mL) did not change, mean edema volume increased by 36% (from 19 to 25 mL, P<0.0001), and mean FDV decreased by 55% (from 14 to 6 mL, P=0.0004) between the acute and subacute phases. Edema volume on the second CT scan correlated positively with FDV on the first SPECT scan (Spearman's p=0.48, P=0.02), and with the volume of reperfused perilesional tissue (FDVacute-FDVsubacute) (Spearman's p=0.41, P=0.05). Perilesional edema on CT always corresponded topographically with perfusion deficits on SPECT. In 4 patients, delayed focal hyperemia was identified in more peripheral cortical regions, but these areas appeared normal on CT. CONCLUSIONS: Perilesional blood flow normalizes from initially depressed levels as edema forms during the first 72 hours after ICH, and the eventual extent of edema correlates with the volume of reperfused tissue. These results suggest that the potential for perilesional ischemia is highest in the earliest hours after ICH onset and implicate reperfusion injury in the pathogenesis of perihematoma edema formation.


Assuntos
Edema Encefálico/diagnóstico por imagem , Edema Encefálico/fisiopatologia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/fisiopatologia , Circulação Cerebrovascular , Doença Aguda , Adulto , Idoso , Encéfalo/irrigação sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
20.
Mol Gen Genet ; 255(5): 514-24, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9294036

RESUMO

Gene expression can be inhibited by antisense RNA transcripts. Although this phenomenon is widely used to analyse gene function in plants, the molecular mechanisms involved are poorly understood. One approach to improving our understanding of antisense gene regulation is to analyse the function of endogenous antisense transcripts. To date, only a small number of plant genes have been shown to be transcribed in both directions and limited information is available concerning the role of natural antisense transcripts in plants. In this study, we have identified several natural antisense transcripts which hybridise to probes derived from the S locus receptor kinase gene (SRK). The RNase protection assay and reverse trancriptase-PCR were used to demonstrate that a proportion of the antisense transcripts are encoded directly by SRK. Using different RNase protection probes, regions of the promoter, exon I (which encodes the S domain) and intron I of SRK were shown to be transcribed in an antisense direction. An antisense SRK transcript was shown to inhibit translation of a sense transcript in vitro. The possible role of antisense SRK transcripts in vivo is discussed.


Assuntos
Brassica/enzimologia , Brassica/genética , Proteínas de Plantas/genética , Proteínas Quinases/genética , RNA Antissenso/genética , RNA de Plantas/genética , Elementos Antissenso (Genética)/genética , Sequência de Bases , DNA de Plantas/genética , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Biossíntese de Proteínas , RNA Mensageiro/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Ribonucleases
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