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BACKGROUND OBJECTIVES: In Port Blair, the capital of Andaman & Nicobar Islands, in the Bay of Bengal, India, there was a sudden increase in fever cases resembling the symptoms of dengue in the monsoon period of 2022. Hence, an investigation was carried out to find out epidemiological and entomological reasons behind the outbreak. METHODS: An entomological survey was carried out in 24 wards of Port Blair Municipal Council (PBMC) area, epidemiological data of last six years (January-December 2017-2021 and January-October 2022) and patient details of the year 2022 were collected. Both the epidemiological and entomological data were analyzed concerning time and place. RESULTS: During this outbreak period tyres (22.4%) came out as a major breeding habitat followed by small discarded materials (17.5%), metal drums (15.3%), and plastic drums (11.7%). In rainy season, peri-domestic breeding (55%) was more than the domestic breeding (45%) habitat. Ae. aegypti had a high preference for indoor large containers (100-1000 L) like plastic tank, metal drum and cement tank whereasAe. albopictus prefers to breed in medium sized plastic container (20-100 L) and outdoor water receptacles like tyres, flower pots, and domestic discarded materials. INTERPRETATION CONCLUSION: By source reduction, indoor space spray and outdoor fogging, vector density was controlled which curtailed the transmission and within eight weeks a decreasing trend of dengue cases was noticed. A regular entomological survey is crucial to know the seasonality and key breeding habitats of the vector for proper planning of vector control.
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Aedes , Dengue , Surtos de Doenças , Ecossistema , Mosquitos Vetores , Estações do Ano , Índia/epidemiologia , Dengue/epidemiologia , Dengue/transmissão , Animais , Humanos , Aedes/virologia , Aedes/fisiologia , Mosquitos Vetores/virologia , Feminino , Masculino , Adulto , Adolescente , Adulto Jovem , Criança , Pessoa de Meia-Idade , Ilhas/epidemiologia , Vírus da Dengue , Pré-EscolarRESUMO
BACKGROUND OBJECTIVES: In Port Blair, the capital of Andaman & Nicobar Islands, in the Bay of Bengal, there was a sudden increase in fever cases resembling the symptoms of dengue in the monsoon period of 2022. Hence, an investigation was carried out to find out both epidemiological and entomological reasons behind the outbreak. METHODS: An Entomological survey was carried out in 24 wards of Port Blair Municipal Council (PBMC) area, epidemiological data of last six years (January to December of 2017-2021 & January to October of 2022) and patient details of the year 2022 were collected. Both the epidemiological and entomological data were analyzed concerning time and place. RESULTS: During this outbreak period tyres (22.4%) came out as a major breeding habitat followed by small discarded materials (17.5%), metal drums (15.3%), and plastic drums (11.7%). In rainy season peri-domestic breeding (55%) was more than the domestic breeding (45%) habitat. Ae. aegypti had a high preference for indoor large containers (100-1000 L) like plastic tank, metal drum and cement tank whereas Ae. albopictus prefers to breed in medium sized plastic container (20-100 L) and outdoor water receptacles like tyres, flower pots, domestic discarded materials etc. INTERPRETATION CONCLUSION: By source reduction, indoor space spray and outdoor fogging vector density was controlled which curtailed the transmission and within 8 weeks decreasing trend of dengue cases were noticed. A regular entomological survey is very important to know the seasonality and key breeding habitats of the vector for proper planning of vector control.
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The incidence of any fracture in the US is estimated to be 2 704 fractures per 100,000 person-years. Approximately 10 percent of these fractures develop complications of healing. The processes that occur during fracture healing mimic the processes that take place in the growth plate during development. The study of fracture healing represents a window to enhance our understanding of the processes of growth and development of bones and its reparative biology. This review is aimed for clinicians evaluating non-unions as an overview of different factors that inhibit fracture healing.
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Consolidação da Fratura/fisiologia , Fraturas Ósseas/fisiopatologia , HumanosRESUMO
UNLABELLED: Previous studies have shown an association between duration of bisphosphonate use and atypical femur fractures. This cohort study showed an increasingly higher risk of subtrochanteric and femoral shaft fractures among those who were more adherent to oral bisphosphonates. INTRODUCTION: Long-term use of oral bisphosphonates has been implicated in an increased risk of atypical femur fractures located in subtrochanteric and femoral shaft regions. Another measure of drug exposure, medication adherence, however, has not been investigated. METHODS: Among all Medicare fee-for-service female beneficiaries from 2006-2010, we followed 522,287 new bisphosphonate users from their index prescription until being censored or having a primary diagnosis of closed subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures. Data about radiographs of fracture site and features were not available. Adherence was classified according to the medication possession ratio (MPR) as the following: MPR < 1/3 as less compliant, MPR ≥ 1/3- < 2/3 as compliant, and MPR ≥ 2/3 as highly compliant. Alternative cutoff points at 50 and 80% were also used. Survival analysis was used to determine the cumulative incidence and hazard of subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures. RESULTS: There was a graded increase in incidence of subtrochanteric/femoral shaft fractures as the level of adherence increased (Gray's test, P < 0.001). The adjusted hazard ratio (HR) for the highly compliant vs. the less compliant was 1.23 (95% Confidence Interval [CI] 1.06-1.43) overall, became significant after 2 years of follow-up (HR = 1.51, 95% CI 1.06-2.15) and reached the highest risk in the fifth year (HR = 4.06, 95% CI 1.47-11.19). However, age-adjusted incidence rates of intertrochanteric/femoral neck fractures were significantly lower among highly compliant beneficiaries, compared to less compliant users (HR = 0.69, 95% CI 0.66-0.73). Similar results were obtained when the cutoff points for being compliant and highly compliant were set at 50 and 80 %, respectively. CONCLUSIONS: Subtrochanteric/femoral shaft fractures, unlike intertrochanteric/femoral neck fractures, are positively associated with higher adherence to long-term (≥3 years) oral bisphosphonates in the elderly female Medicare population.
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Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Fraturas do Fêmur/induzido quimicamente , Adesão à Medicação/estatística & dados numéricos , Osteoporose Pós-Menopausa/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Fraturas do Fêmur/epidemiologia , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/etiologia , Fraturas do Colo Femoral/prevenção & controle , Fraturas do Quadril/induzido quimicamente , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Humanos , Incidência , Medicare , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle , Estudos Retrospectivos , Estados Unidos/epidemiologiaRESUMO
AIMS: There is evidence that proper radiotherapy trial quality assurance (RTTQA) translates into improved outcomes for patients. However, the practice of RTTQA is heterogeneous and implemented in a diverse manner across trials. In this paper, we review the RTTQA report for randomised trials (RCT) conducted in India and present our experience with RTTQA for various clinical trials and highlight the key achievements and challenges. MATERIALS AND METHODS: Search was performed using the keywords and the variations thereof for "radiotherapy" and author affiliations from India, its states and major metropolitan cities. Pubmed search filters were used to restrict results to RCT published in the past 5 years (2019-2024). Reporting of RTTQA procedures from publications and protocols was documented along with the protocol-specified dosimetric goals. We also evaluated a few clinical trials performed in the Department of Radiation Oncology at Tata Medical Center. The different RTTQA procedures and results for four representative clinical trials have been described. RESULTS: A formal RTTQA process was reported by only one out of 24 randomised controlled trials and formal dosimetric goals were pre-specified by 9 of 13 trials where IMRT was used as treatment. RTTQA requirements were tailored for each clinical trial at Tata Medical Center. For the HYPORT trial, the RTTQA process focused on ensuring the matchline doses were homogenous. HYPORT B trial commissioned the use of a simultaneous integrated boost technique which emphasised conformal avoidance of dose spillage to contralateral breast and lung. HYPORT Adjuvant and PROPARA trials are multicentre clinical trials. While HYPORT Adjuvant focussed on ensuring that the dose delivery met the predefined constraints, segmentation of the target volume was important for the PROPARA trial. CONCLUSION: We demonstrate different RTTQA procedures required for representative clinical trials and highlight key challenges encountered.
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BACKGROUND: Clear cell renal cell carcinoma (CCRCC) is the commonest form of kidney cancer. Up to 91% have biallelic inactivation of VHL, resulting in stabilisation of HIF-α subunits. Factor inhibiting HIF-1 is an enzyme that hydroxylates HIF-α subunits and prevents recruitment of the co-activator CBP/P300. An important question is whether FIH-1 controls HIF activity in CCRCC. METHODS: Human VHL defective CCRCC lines RCC10, RCC4 and 786-O were used to determine the role of FIH-1 in modulating HIF activity, using small interfering RNA knockdown, retroviral gene expression, quantitative RT-PCR, western blot analysis, Annexin V and propidium iodide labelling. RESULTS: Although it was previously suggested that FIH-1 is suppressed in CCRCC, we found that FIH-1 mRNA and protein are actually present at similar levels in CCRCC and normal kidney. The FIH-1 inhibition or knockdown in the VHL defective CCRCC lines RCC10 and RCC4 (which express both HIF-1α and HIF-2α) resulted in increased expression of HIF target genes. In the 786-O CCRCC cell line, which expresses only HIF-2α, FIH-1 attenuation showed no significant effect on expression of these genes; introduction of HIF-1α resulted in sensitivity of HIF targets to FIH-1 knockdown. In RCC4 and RCC10, knockdown of FIH-1 increased apoptosis. Suppressing HIF-1α expression in RCC10 prevented FIH-1 knockdown from increasing apoptosis. CONCLUSION: Our results support a unifying model in which HIF-1α has a tumour suppressor action in CCRCC, held in check by FIH-1. Inhibiting FIH-1 in CCRCC could be used to bias the HIF response towards HIF-1α and decrease tumour cell viability.
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Apoptose , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Neoplasias Renais/patologia , Aminoácidos Dicarboxílicos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular , Citoproteção , Humanos , Oxigenases de Função Mista , Proteínas Repressoras/fisiologia , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologiaRESUMO
Hepatocarcinogenesis was induced in Sprague Dawley rats by injecting diethylnitrosamine (DENA); 150 mg/kg body weight, ip, a well known liver carcinogen and a mutagenic agent. Concurrent with the induction of hepatocarcinoma, psychological stress was also elicited from the changes in brain neurotransmitters. Noradrenaline and dopamine, the neurotransmitters of sympathetic system were estimated from the whole brain and corresponding hormones T3, T4 and prolactin were estimated from the blood of such rats. The neuroendocrine cascade and the marker enzyme gamma glutamyl transferase were estimated at 7, 14, 21 and 30 weeks. A direct relationship between noradrenaline, T3 and T4 and a reciprocal relationship between dopamine and prolactin were observed, which may be correlated to the carcinogenic effect of DENA.
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Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/metabolismo , Dietilnitrosamina/farmacologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/metabolismo , Sistemas Neurossecretores/efeitos dos fármacos , Sistemas Neurossecretores/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Dopamina/metabolismo , Masculino , Norepinefrina/metabolismo , Prolactina/sangue , Ratos , Ratos Sprague-Dawley , gama-Glutamiltransferase/metabolismoRESUMO
BACKGROUND: To predict the neonatal outcome in high risk obstetric cases by admission cardiotocography (CTG) testing. METHODS: A total of 150 consecutive high risk obstetric patients meeting the inclusion criteria were subjected to admission CTG testing in this prospective study. The CTG tracing was categorized based on Royal College of Obstetricians and Gynaecologists (RCOG) criteria. Specific foetal and neonatal outcome measures were studied and correlated with the admission CTG testing. RESULT: Foetal distress during labour developed in 15% of patients with a normal test and in 73% of patients with an abnormal test. The admission test had a sensitivity of 66.7%, specificity of 93.3% and a positive predictive value of 53.3% for predicting an Apgar score < 5 at birth. Neonatal admission to neonatal intensive care unit was required in 1% of patients with a normal test and 33% of patients with an abnormal test (p <0.01). CONCLUSION: The result of admission cardiotocography testing could be used to identify patients likely to develop adverse foetal outcomes and help in optimal utilization of labour room resources.
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BACKGROUND: The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival. METHODS: Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period. RESULTS: A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest. CONCLUSION: The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.
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Acute abdomen in pregnancy is due to consequence of pregnancy itself or is totally unrelated to pregnancy. During pregnancy, a woman is at an increased risk of acute abdomen due to various physiological changes. The article discusses the various conditions which can present as acute abdomen in women during pregnancy and in non-pregnant state. The clinician often has a difficult task in diagnosing and managing acute abdomen in pregnancy. Clinical evaluation is further confounded by various anatomical and physiological changes occurring in pregnancy. The growing gravid uterus too causes difficulty in detailed examination. The general reluctance to use conventional X-rays because of pregnancy should be set aside when faced with a seriously ill mother. A reluctance to operate during pregnancy adds unnecessary delay, which increases morbidity for both the mother and the fetus. Adnexal accidents should always be kept in mind in a woman with acute abdomen even if she is not pregnant. Such mistakes should be avoided as prompt diagnosis and appropriate therapy are crucial. A general approach to acute abdominal conditions in pregnancy is to manage these problems considering the risk to mother regardless of the pregnancy.
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The Kolkata superconducting cyclotron utilises liquid helium to cool the main magnet niobium-titanium (NbTi) coil and the cryopanels. Three liquid helium cooled cryopanels, placed inside the dees of the radio-frequency system, maintain the high vacuum in the acceleration region of the superconducting cyclotron. The small cryostat placed inside the cryogenic distribution manifold located at the basement of the superconducting cyclotron building supplies liquid helium in parallel branches to three cold heads, used for cooling their associated cryopanels. The level in the cryostat has to be maintained at an optimum value to ensure uninterrupted flow of liquid helium to these three cold heads. This paper describes the transfer function of the overall system, its tuning parameters, and discusses the actual control of cryostat level by using these parameters.
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Conformational changes that occur upon substrate binding are known to play crucial roles in the recognition and specific aminoacylation of cognate tRNA by glutaminyl-tRNA synthetase. In a previous study we had shown that glutaminyl-tRNA synthetase labeled selectively in a nonessential sulfhydryl residue by an environment sensitive probe, acrylodan, monitors many of the conformational changes that occur upon substrate binding. In this article we have shown that the conformational change that occurs upon tRNA(Gln) binding to glnRS/ATP complex is absent in a noncognate tRNA tRNA(Glu)-glnRS/ATP complex. CD spectroscopy indicates that this cognate tRNA(Gln)-induced conformational change may involve only a small change in secondary structure. The Van't Hoff plot of cognate and noncognate tRNA binding in the presence of ATP is similar, suggesting similar modes of interaction. It was concluded that the cognate tRNA induces a local conformational change in the synthetase that may be one of the critical elements that causes enhanced aminoacylation of the cognate tRNA over the noncognate ones.
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Aminoacil-tRNA Sintetases/química , Conformação Proteica , RNA de Transferência de Glutamina/metabolismo , 2-Naftilamina/análogos & derivados , 2-Naftilamina/metabolismo , Trifosfato de Adenosina/metabolismo , Dicroísmo Circular , Fluorescência , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , RNA de Transferência de Ácido Glutâmico/metabolismo , Especificidade por Substrato , TemperaturaRESUMO
The susceptibility of cortical neurons to two forms of apoptotic death was compared with susceptibility to excitotoxic death during development in vitro (DIV 4-21). Murine cortical cultures were exposed for 48 h to the phosphatase inhibitor cyclosporine, the protein kinase inhibitor staurosporine or the excitotoxin N-methyl-D-aspartate (NMDA). Susceptibility to apoptosis induced by staurosporine or cyclosporine was maximal between DIV 4-10 and declined from DIV 10 through 18. The opposite pattern was observed with susceptibility to NMDA receptor-mediated excitotoxic necrosis, which was minimal at DIV 6 and progressively increased through DIV 21.
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Apoptose/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Ciclosporina/farmacologia , N-Metilaspartato/farmacologia , Neurônios/efeitos dos fármacos , Animais , Apoptose/fisiologia , Células Cultivadas/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , CamundongosRESUMO
Rabbit polyclonal antibodies against the lipopolysaccharide of Escherichia coli O126 were serologically characterized by ELISA. The antibody specificities were determined by studying the inhibitory effects of the methyl glycosides of both anomeric configurations of the constituent monosaccharides and the oligosaccharides derived from the O-antigenic polysaccharide of E. coli O126. It was found that, amongst the monosaccharides, beta-D-N-acetyl glucosamine was the most effective inhibitory sugar in the O126 polysaccharide and the major specificity of the polyclonal antibodies was found to be directed against the trisaccharide having the structure alpha-D-Galp (1-->3)-beta-D-GlcpNAc(1-->2)-D-Manp.
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Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Escherichia coli/imunologia , Polissacarídeos Bacterianos/imunologia , Animais , Sequência de Carboidratos , Ensaio de Imunoadsorção Enzimática , Soros Imunes , Immunoblotting , Dados de Sequência Molecular , Monossacarídeos/imunologia , Antígenos O , Oligossacarídeos/imunologia , CoelhosRESUMO
The immunodominant part in the O-antigenic polysaccharide from Escherichia coli O128 was immunologically characterized by an enzyme-linked immunosorbent assay (ELISA). The antibody specificity was determined by the inhibitory effects of the methyl glycosides of constituent mono- and oligosaccharides synthesized related to the O-antigenic polysaccharide from E. coli O128. It was found that methyl alpha-L-fucopyranoside was the most effective inhibitor amongst the monosaccharides while the highest antibody specificity was directed towards the trisaccharide with the structure: beta-D-GalpNAc-(1-->6)-[alpha-L-Fucp-(1-->2)]-beta-D-Galp-1-->OMe suggesting that the monospecific antibody has the extended combining site.
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Escherichia coli/imunologia , Epitopos Imunodominantes/análise , Antígenos O/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Reações Antígeno-Anticorpo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Glicosídeos/farmacologia , Humanos , Imunoglobulina G/imunologia , Recém-Nascido , Monossacarídeos/farmacologia , Oligossacarídeos/farmacologia , CoelhosRESUMO
In this study codon usage bias of all experimentally known genes of Lactococcus lactis has been analyzed. Since Lactococcus lactis is an AT rich organism, it is expected to occur A and/or T at the third position of codons and detailed analysis of overall codon usage data indicates that A and/or T ending codons are predominant in this organism. However, multivariate statistical analyses based both on codon count and on relative synonymous codon usage (RSCU) detect a large number of genes, which are supposed to be highly expressed are clustered at one end of the first major axis, while majority of the putatively lowly expressed genes are clustered at the other end of the first major axis. It was observed that in the highly expressed genes C and T ending codons are significantly higher than the lowly expressed genes and also it was observed that C ending codons are predominant in the duets of highly expressed genes, whereas the T endings codons are abundant in the quartets. Abundance of C and T ending codons in the highly expressed genes suggest that, besides, compositional biases, translational selection are also operating in shaping the codon usage variation among the genes in this organism as observed in other compositionally skewed organisms. The second major axis generated by correspondence analysis on simple codon counts differentiates the genes into two distinct groups according to their hydrophobicity values, but the same analysis computed with relative synonymous codon usage values could not discriminate the genes according to the hydropathy values. This suggests that amino acid composition exerts constraints on codon usage in this organism. On the other hand the second major axis produced by correspondence analysis on RSCU values differentiates the genes into two groups according to the synonymous codon usage for cysteine residues (rarest amino acids in this organism), which is nothing but a artifactual effect induced by the RSCU values. Other factors such as length of the genes and the positions of the genes in the leading and lagging strand of replication have practically no influence in the codon usage variation among the genes in this organism.
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Códon , Código Genético , Lactococcus lactis/genética , Análise MultivariadaRESUMO
The surface preparation technique was used for a study of cochlear hair cell loss as a function of age in rabbits 1 week, 6 months, 1 year, and 4 years old. Cytocochleograms from these animals were prepared which indicated damaged or missing hair cells over the entire spiral organ from the apical to the basal coil. The loss in the mean percentage of total outer hair cells (OHC) and inner hair cells (IHC) appeared to increase linearly with increasing age, with a statistically significant correlation. The cell loss was similar in all three rows of OHC in each of the age groups. In animals up to 1 year of age, areas of OHC loss were localized in the apical and basal coils. In 4-year-old rabbits, OHC degeneration had become progressively accentuated and widespread. The pattern of IHC loss was somewhat similar to that of OHC. Age-related hair cell loss in the rabbit is comparable to that in the rat, monkey, and human cochlea.
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Envelhecimento/fisiologia , Cóclea/crescimento & desenvolvimento , Células Ciliadas Auditivas/patologia , Animais , Atrofia , Contagem de Células , Cóclea/patologia , Células Ciliadas Auditivas/fisiologia , CoelhosRESUMO
The ultrastructural characteristics of the interrenal cell were investigated in the quail and the pigeon after fixation by intravascular abdominal perfusion. There is no significant fine structural difference between cells belonging to subcapsular and central regions of the gland. The interrenal cell in both species possesses nuclear bodies, polymorphic mitochondria with tubulo-vesicular cristae and tubular crystalline inclusions, considerable amounts of endoplasmic reticulum, ergastoplasm, a well developed Golgi apparatus, coated vesicles, microtubules, filaments, cilia, ribosomes, a profusion of liposomes, dense bodies with varied inner structure, pinocytic invaginations of cell membrane and intercellular attachment devices. The pigeon adrenorcortical cell also possesses intranuclear lipidlike inclusions and fibrous bundle (this being never recorded in adrenocortical cell), annulate lamellae, and a variety of cytosomes, probably lipofucsin in nature. The significance and cytophysiological role of various organelles and inclusions have been discussed in the light of earlier data obtained on avian adrenocortical cells.
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Córtex Suprarrenal/ultraestrutura , Glândulas Suprarrenais/ultraestrutura , Columbidae/anatomia & histologia , Coturnix/anatomia & histologia , Codorniz/anatomia & histologia , Animais , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Cílios/ultraestrutura , Corpos de Inclusão/ultraestrutura , Lipídeos/análise , Lipofuscina/análise , Mitocôndrias/ultraestrutura , Organoides/ultraestruturaRESUMO
OBJECTIVES: To examine the effects of fibrinogen concentration and application thickness of fibrin tissue adhesive on skin graft survival. STUDY DESIGN: Prospective controlled study. METHODS: Ten domestic pigs were included in the study. A 20 x 5-cm area of skin was harvested bilaterally along the flanks of the animals using a Padgett dermatome. The harvested grafts were trimmed into four 4 x 4-cm squares. Donor sites were treated according to group assignment and the non-meshed grafts were placed on the side opposite their initial orientation and secured with staples. Both single- and multiple-donor human fibrin tissue adhesive preparations, with low and high average fibrinogen concentrations of 30 mg/mL and 60 mg/ mL, were used. Adhesive preparations were applied in either a thin layer (0.015 mL/cm2) or a thick layer (0.06 mL/cm2) using a spray applicator. A constant thrombin concentration of 10 U/mL was used in the study. No adhesive was used in the control group and grafts were stabilized with staples. No topical dressings were applied to any of the treatment sites. Animals were sacrificed 4 weeks after graft application. RESULTS: Based on statistical analysis, thickness of adhesive application had a significant effect on skin graft survival. Percent mean graft survival in the control and thin application groups was found to be 92% and 97.8% respectively; the mean survival rate in the thick application group was 63.1%. Fibrinogen concentration, when evaluated independently within the thin and thick application groups, was found to have no significant effect on graft survival. CONCLUSION: Independent of fibrinogen concentration, a thin layer of fibrin tissue adhesive, when applied between two opposing surfaces, does not interfere with and may support the healing process, whereas a thick layer of adhesive inhibits skin graft healing.
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Adesivo Tecidual de Fibrina/administração & dosagem , Fibrinogênio/administração & dosagem , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Pele/fisiologia , Cicatrização/efeitos dos fármacos , Animais , Avaliação Pré-Clínica de Medicamentos , Adesivo Tecidual de Fibrina/química , Adesivo Tecidual de Fibrina/farmacologia , Fibrinogênio/farmacologia , Suínos , Cicatrização/fisiologiaRESUMO
OBJECTIVE: Recently, a two-dimensional Silastic Dacron stretching skin device has been developed for scalp reduction surgery. Attached subgaleally, this device stretches skin over time, while avoiding the visible volumetric distention that is typical of three-dimensional tissue expanders. Unlike three-dimensional expanders, the histological changes observed with a two-dimensional stretching device have not been described in the literature. The present study compares the histological effects of two-dimensional and three-dimensional skin tissue expansion in the porcine model. STUDY DESIGN: A university Institutional Review Board-approved study in which 16 domestic piglets were used. The 16 piglets were divided evenly into four cohorts as follows: 1, 1-week control cohort; 2, 1-week experimental cohort; 3, 4-week control cohort; and 4, 4-week experimental cohort. METHODS: Tissue expanders (three-dimensional) and Dacron Silastic tissue stretchers (two-dimensional) were surgically inserted into the lateral skin of 16 domestic pigs. Animals were killed at either 1 or 4 weeks based on group assignment. Light microscopic ocular micrometry and stereological point counting were used to determine the depth of the epidermis, dermis, and subdermal adipose tissue layer; width of the panniculus muscle; diameter of sweat gland follicles; percentage ratio of dermal collagen, blood vessels, and tissue space; and epidermal mitotic index in 100 specimens. One-way ANOVA was used to evaluate statistical differences. RESULTS: Both tissue expanders yielded increased values compared with control subjects, with respect to epidermal, dermal, and fat widths and blood vessel counts, whereas adnexal structures in the panniculus muscle width were unaltered. CONCLUSIONS: Although statistically the two types of expansion produced histologically similar changes, the degree of change varied according to the type of expander that was used and the duration of tissue expansion. Most notably, three-dimensional expansion produced more tissue gain per unit area expanded at both the 1-week and the 4-week time intervals, and early (1-week) two-dimensional tissue expansion stimulated a greater angiogenic response than three-dimensional expansion. These findings will assist the surgeon in understanding the physical changes that occur with these two forms of tissue expansion, as well as the potential clinical advantages and shortcomings of each method.