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1.
J Fish Biol ; 103(6): 1300-1311, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37596740

RESUMEN

Larval attachment organs (LAOs) are unicellular or multicellular organs that enable the larvae of many actinopterygian fishes to adhere to a substrate before yolk-sac absorption and the free-swimming stage. Bowfins (Amiiformes) exhibit a sizable LAO on the snout, which was first described in the late 19th and early 20th centuries. In this study, we document the LAO of Amia ocellicauda (Richardson, 1836) using a combination of scanning electron microscopy (SEM) and light microscopy, and histochemistry. We examined material representing three stages with SEM ranging in size from 5.8 to 11.2 mm in notochord length and one stage histochemically. We compare the LAO of A. ocellicauda to that of the lepisosteid Atractosteus tropicus Gill, 1863 and show that although the LAOs of A. ocellicauda and A. tropicus are both super-organs, the two differ in the ultrastructure of the entire organ. A. ocellicauda possesses two distinct lobes, with the organs arranged on the periphery with none in the middle, whereas A. tropicus also possesses two lobes, but with the organs scattered evenly across the super-organ. The individual organs of A. ocellicauda possess adhesive cells set deep to support cells with the adhesive substance released through a pore, whereas A. tropicus possesses both support cells and adhesive cells sitting at a similar level, with the adhesive substance released directly onto the surface of the organ. We additionally provide a table summarizing vertebrate genera in which attachment organs have been documented and discuss the implications of our study for hypotheses of the homology of attachment organs in the Holostei.


Asunto(s)
Peces , Animales , Larva , Filogenia , Microscopía Electrónica de Rastreo
2.
AJNR Am J Neuroradiol ; 44(6): 681-686, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37169538

RESUMEN

BACKGROUND AND PURPOSE: IV thrombolysis with alteplase before mechanical thrombectomy for emergent large-vessel-occlusion stroke is associated with access-site bleeding complications. However, the incidence of femoral access-site complications with tenecteplase before mechanical thrombectomy requires exploration. Here, femoral access-site complications with tenecteplase versus alteplase before mechanical thrombectomy for large-vessel-occlusion stroke were compared. MATERIALS AND METHODS: All patients receiving IV thrombolytics before mechanical thrombectomy for large-vessel-occlusion stroke who presented from January 2020 to August 2022 were reviewed. In May 2021, our health care system switched from alteplase to tenecteplase as the primary thrombolytic for all patients with stroke, facilitating the comparison of alteplase-versus-tenecteplase femoral access-site complication rates. Major (requiring surgery) and minor (managed conservatively) access-site complications were assessed. RESULTS: One hundred thirty-nine patients underwent transfemoral mechanical thrombectomy for large-vessel-occlusion stroke, of whom 46/139 (33.1%) received tenecteplase and 93/139 (66.9%) received alteplase. In all cases (n = 139), an 8F sheath was inserted without sonographic guidance, and vascular closure was obtained with an Angio-Seal. Baseline demographics, concomitant antithrombotic medications, and periprocedural coagulation lab findings were similar between groups. The incidence of conservatively managed groin hematomas (2.2% versus 4.3%), delayed access-site oozing requiring manual compression (6.5% versus 2.2%), and arterial occlusion requiring surgery (2.2% versus 1.1%) was similar between the tenecteplase and alteplase groups, respectively (P = not significant). No dissection, arteriovenous fistula, or retroperitoneal hematoma was observed. CONCLUSIONS: Tenecteplase compared with alteplase before mechanical thrombectomy for large-vessel-occlusion stroke is not associated with an alteration in femoral access-site complication rates.


Asunto(s)
Arteriopatías Oclusivas , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Activador de Tejido Plasminógeno/uso terapéutico , Tenecteplasa/uso terapéutico , Isquemia Encefálica/complicaciones , Resultado del Tratamiento , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular Isquémico/complicaciones , Trombectomía/efectos adversos , Arteriopatías Oclusivas/complicaciones
4.
J Fish Biol ; 100(3): 852-855, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35038175

RESUMEN

The eyes of teleostean fishes typically exhibit two ossifications, the anterior and posterior sclerotics, both associated with the scleral cartilage. The West African Denticle herring Denticeps clupeoides has three scleral ossifications, including the typical two associated with the scleral cartilage (anterior and posterior sclerotic) and a third ossification (Di Dario's ossicle), spatially separated from the scleral cartilage and located within the anteromedial wall of the sclera. The medial rectus muscle inserts on the medial surface of Di Dario's ossicle, suggesting that this third sclerotic may play a role in forward rotation of the eye in this surface feeding fish.


Asunto(s)
Calcificaciones de la Pulpa Dental , Esclerótica , Animales , Peces , Osteogénesis , Alimentos Marinos
5.
Odontology ; 109(4): 802-811, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34047872

RESUMEN

The purpose is to evaluate the antibacterial effects of the silver nanoparticles (AgNPs) (Nanografi, METU Teknokent, Ankara, Turkey) mixed with calcium hydroxide (Ca(OH)2) (Ultracal XS, Ultradent, St Louis, US) or chlorhexidine gel (CHX) (Gluco-Chex, Cerkamed, Stalowa Wola, Poland) against a multispecies biofilm, by confocal laser scanning microscopy (CLSM) and culture-based analysis. Dentine blocks were inoculated with Enterococcus faecalis, Streptococcus mutans, Lactobacillus acidophilus and Actinomyces naeslundii for 1 week. Infected dentine blocks were randomly divided into groups according to medication; saline solution (SS), Ca(OH)2, Ca(OH)2 + AgNP, 2%CHX gel and 2%CHX gel + AgNP and time of application: 1 and 7 days (all groups, n = 5). Bacterial samples were collected before and after medication to quantify the bacterial load. Biofilm elimination was quantitatively analyzed by Live/Dead BacLight Bacterial Viability staining and CLSM. The addition of AgNPs to Ca(OH)2 increased the effectiveness of medicament in terms of bacterial reduction in both application times (1 and 7 days) (p < 0.05: ANOVA, Tukey's test) according to culture-based analysis. The CLSM images revealed that mixture of AgNP with CHX killed significantly more bacteria when compared with all other medicaments at 1- and 7-day application times (p < 0.05 and p > 0.05, respectively: Kruskal-Wallis, Dunn post hoc tests). The efficacy of Ca(OH)2 mixed with AgNPs was superior to Ca(OH)2 used alone in both application times (p < 0.05) according to CLSM analysis. The present study put forth the potential use of AgNPs mixed with Ca(OH)2 or CHX on multispecies (Enterococcus faecalis, Streptococcus mutans, Lactobacillus acidophilus and Actinomyces naeslundii) biofilm in 1 and 7day application periods.


Asunto(s)
Clorhexidina , Nanopartículas del Metal , Actinomyces , Antibacterianos/farmacología , Biopelículas , Hidróxido de Calcio/farmacología , Clorhexidina/farmacología , Dentina , Irrigantes del Conducto Radicular , Plata/farmacología
6.
AJNR Am J Neuroradiol ; 41(9): 1677-1682, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32616585

RESUMEN

Coronavirus disease 2019 (COVID-19) is associated with a severe inflammatory response. Inflammation affects atherosclerotic plaque vulnerability and promotes a thrombogenic environment. We report a series of 6 patients with COVID-19 with acute ischemic stroke due to intraluminal carotid artery thrombus presenting during an 8-day period. Six patients were included (5 men) with a mean age of 65.8 years (range, 55-78 years). COVID-19 was diagnosed by detection of Severe Acute Respiratory Syndrome coronavirus 2 in 5 patients and was presumed due to typical clinical and imaging findings in 1 patient. All patients had vascular risk factors including diabetes (83%), hyperlipidemia (100%), and smoking (17%). Four patients presented with large infarcts with initial NIHSS scores of 24-30. During their hospitalization, all patients had elevated D-dimer and C-reactive protein levels, 5 patients had elevated lactate dehydrogenase and ferritin levels, 3 had elevated interleukin-6 levels, and 2 had elevated troponin levels. Inflammation related to COVID-19 may result in rupture of vulnerable atherosclerotic plaques, resulting in thrombosis and acute ischemic stroke.


Asunto(s)
Betacoronavirus , Isquemia Encefálica/etiología , Arterias Carótidas/diagnóstico por imagen , Infecciones por Coronavirus/complicaciones , Citocinas/inmunología , Neumonía Viral/complicaciones , Accidente Cerebrovascular/etiología , Trombosis/etiología , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/inmunología , COVID-19 , Angiografía por Tomografía Computarizada , Infecciones por Coronavirus/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/inmunología , Factores de Riesgo , SARS-CoV-2 , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/inmunología , Trombosis/diagnóstico por imagen , Trombosis/inmunología
7.
AJNR Am J Neuroradiol ; 41(5): 822-827, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32414902

RESUMEN

BACKGROUND AND PURPOSE: Previous studies in acute ischemic stroke have demonstrated the importance of minimizing delays to endovascular treatment and keeping thrombectomy procedural times at <30-60 minutes. The purpose of this study was to investigate the impact of thrombectomy procedural times on clinical outcomes. MATERIALS AND METHODS: We retrospectively compared 319 patients having undergone thrombectomy according to procedural time (<30 minutes, 30-60 minutes, and >60 minutes) and time from stroke onset to endovascular therapy (≤6 or >6 hours). Clinical characteristics of patients with postprocedural intracranial hemorrhage were also assessed. Logistic regression was used to determine independent predictors of poor outcome at 90 days (mRS ≥3). RESULTS: Greater age (OR, 1.03; 95% CI, 1.01-1.06; P = .016), higher admission NIHSS score (OR, 1.10; 95% CI, 1.04-1.16; P = .001), history of diabetes mellitus (OR, 1.96; 95% CI, 1.05-3.65; P = .034), and postprocedural intracranial hemorrhage were independently associated with greater odds of poor outcome. Modified TICI scale scores of 2c (OR, 0.11; 95% CI, 0.04-0.28; P < .001) and 3 (OR, 0.15; 95% CI, 0.06-0.38; P < .001) were associated with reduced odds of poor outcome. Although not statistically significant on univariate analysis, onset to endovascular therapy of >6 hours was independently associated with increased odds of poor outcome (OR, 2.20; 95% CI, 1.11-4.36; P = .024) in the final multivariate model (area under the curve = 0.820). Procedural time was not independently associated with clinical outcome in the final multivariate model (P > .05). CONCLUSIONS: Thrombectomy procedural times beyond 60 minutes are associated with lower revascularization rates and worse 90-day outcomes. Procedural time itself was not an independent predictor of outcome. While stroke thrombectomy procedures should be performed rapidly, our study emphasizes the significance of achieving revascularization despite the requisite procedural time. However, the potential for revascularization must be weighed against the risks associated with multiple thrombectomy attempts.


Asunto(s)
Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Tiempo de Tratamiento , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
9.
J Morphol ; 280(3): 339-359, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30667538

RESUMEN

The characteristic and morphologically variable pectoral-fin spine of catfishes (order Siluriformes) has been well-investigated based on later developmental stages (juveniles and adults) but information on the earliest life stages are lacking. Here, we document the ontogeny of pectoral-fin spines in four siluroid (Ictalurus punctatus, Noturus gyrinus, Silurus glanis and Akysis vespa) and two loricarioid catfishes (Corydoras panda and Ancistrus sp.). To further our understanding of pectoral-fin spine development, we also examined adult and juvenile specimens representing 41 of the currently 43 recognized families of catfishes. Development of the pectoral-fin spine is similar in all catfishes and resembles the development of a typical soft fin ray. Fusion between hemitrichia of the anteriormost lepidotrichium occurs proximally first, forming the spine proper, with growth of the spine occurring through the subsequent fusion of developing distal hemitrichial segments that comprise the spurious ray. The variation of pectoral-fin spine morphology observed is largely attributed to the presence/absence of five traits, which either develop as part of the hemitrichial segments that are added to the distal tip of the spine during growth (distal rami, anterior/posterior serrae) or develop independent of these segments (denticuli and odontodes).


Asunto(s)
Aletas de Animales/embriología , Bagres/embriología , Animales , Fenotipo
10.
Int Endod J ; 52(1): 77-85, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29985531

RESUMEN

AIM: To evaluate the bacterial reduction achieved by WaveOne Gold (Dentsply Sirona Endodontics, Ballaigues, Switzerland), Hyflex EDM (Coltene-Whaledent, Altstätten, Switzerland), and XP-endo Shaper (FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) in canals infected with Enterococcus faecalis. The null hypothesis (H0 ) was that there would be no difference amongst the NiTi systems in reducing the root canal bacterial load. METHODOLOGY: Seventy-four mandibular premolar teeth with straight and round root canals were selected. Sixty-two root canals were contaminated with E. faecalis for 4 weeks and subjected to mechanical preparation with one of three single-file NiTi rotary systems (WaveOne Gold, Hyflex EDM, and XP Endo Shaper). Twelve non-contaminated root canals were used as negative controls. Bacterial samples were collected with sterile paper points (Dentsply Sirona Endodontics) before and after rotary instrumentation to quantify the bacterial load. Five roots from each instrumentation group were evaluated topographically from the coronal, middle and apical thirds by SEM. The bacterial reduction was calculated and analysed statistically by the Kruskal-Wallis and Dunn post hoc tests, all at 5% significance. RESULTS: The samples taken before instrumentation showed approximately 9.64 log CFU bacterial load. Instrumentation with the Hyflex EDM and XP-endo Shaper resulted in significantly greater bacterial reduction than those with WaveOne Gold (P = 0.00). All specimens had bacterial growth. SEM images supported the CFU/mL data. Thick and dense debris was observed in WaveOne Gold samples. Instrumentation resulted in the disruption of the biofilm-like structure, and both areas of clean and open dentinal tubules and areas with thick debris were observed in Hyflex EDM and XP-endo Shaper samples. CONCLUSIONS: Instrumentation in straight and round canals of premolar teeth with the Hyflex EDM and XP-endo Shaper resulted in significantly greater bacterial reduction than WaveOne Gold. No instrumentation system rendered root canals completely free from bacteria.


Asunto(s)
Carga Bacteriana , Instrumentos Dentales , Cavidad Pulpar/microbiología , Enterococcus faecalis , Preparación del Conducto Radicular/instrumentación , Diente Premolar , Biopelículas , Dentina/diagnóstico por imagen , Dentina/patología , Enterococcus faecalis/crecimiento & desarrollo , Diseño de Equipo , Humanos , Níquel , Preparación del Conducto Radicular/métodos , Propiedades de Superficie , Titanio
11.
AJNR Am J Neuroradiol ; 39(12): 2270-2277, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30385475

RESUMEN

BACKGROUND AND PURPOSE: Although covered side branches typically remain patent acutely following Pipeline Embolization Device embolization of intracranial aneurysms, the long-term fate of these vessels remains uncertain. We therefore elected to investigate factors that may influence the long-term patency of these covered side branches. MATERIALS AND METHODS: We retrospectively evaluated the long-term patency of side branches covered by the Pipeline Embolization Device at our institution during treatment of intracranial aneurysms with at least 6 months of conventional angiography follow-up. Procedural and anatomic factors that might influence the fate of covered side branches were explored. RESULTS: One hundred forty-eight Pipeline Embolization Device treatments in 137 patients met the inclusion criteria. In 217 covered side branches, 29 (13.4%) were occluded on follow-up, and 40 (18.4%) were stenotic. All stenoses and occlusions were asymptomatic. In the entire cohort and in the largest subset of ophthalmic arteries, a smaller Pipeline Embolization Device diameter was associated with branch vessel occlusion (P = .001, P = .013). When we considered stenotic and occluded side branches together, smaller Pipeline Embolization Device size (P = .029) and administration of intraprocedural abciximab (P = .03) predicted side branch stenosis/occlusion, while anterior choroidal branch type (P = .003) was a predictor of gross side branch patency. CONCLUSIONS: A smaller Pipeline Embolization Device diameter is associated with delayed side branch stenosis/occlusion following Pipeline Embolization Device treatment, likely due to the higher metal density of smaller caliber devices. Although hemodynamic factors, including the potential for collateral flow, are still paramount in determining the fate of covered side branches, the amount of metal coverage at the side branch orifice also plays an important role.


Asunto(s)
Arterias Cerebrales/patología , Embolización Terapéutica/instrumentación , Aneurisma Intracraneal/terapia , Grado de Desobstrucción Vascular , Adulto , Anciano , Prótesis Vascular , Angiografía Cerebral , Constricción Patológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
12.
Neotrop. ichthyol ; 16(1): e170014, 2018. graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-895133

RESUMEN

We document for the first time the early ontogeny of Centropomus poeyi based on captive raised material representing 0-19 days posthatch (dph). The achievement of early developmental landmarks (i.e., yolk-sac depletion, flexion, development of fins) and changes in pigmentation are described (1.4 mm NL-10.6 mm SL; 0-19 dph) and documented for a subset of individuals using high quality photographs. The ontogeny of the viscerocranium is also described (2.4 mm NL-10.6 mm SL; 6-19 dph). Development in C. poeyi occurs over a short period with attainment of the juvenile stage (i.e., full complement of fin rays present in each fin) occurring by 6.9 mm SL. The ontogeny of external pigmentation in C. poeyi is marked by two trends throughout growth: (1) a decrease in pigmentation dorsally; and (2) an increase in pigmentation ventrally along the midline. Development of the viscerocranium begins with the appearance of the maxilla and dentary in individuals of 2.4 mm NL, coinciding with the depletion of the yolk-sac. By 10.6 mm SL all bones of the viscerocranium are present and teeth are present on all teeth-bearing bones of the adult. Aspects of early development in C. poeyi are compared with the congeners C. undecimalis and C. parallelus.(AU)


Se documentó por primera vez la ontogenia temprana de Centropomus poeyi basada en material obtenido de cautiverio a partir de embriones (0 días después de la eclosión, dde) hasta los 19 dde. Se registró la aparición de puntos de referencia en el desarrollo temprano (p.ej. consumo de saco vitelino, flexión, desarrollo de aletas) y los cambios de pigmentación han sido descritos (1.4 mm NL-10.6 mm SL; 0-19 dde), siendo documentado para un subgrupo de individuos utilizando fotografías de alta calidad. El desarrollo del viscerocráneo también fue descrita (2.4 mm NL-10.6 mm SL; 6-19 dde). El desarrollo en C. poeyi sucede en un periodo corto de tiempo hasta alcanzar una etapa juvenil (p.ej., aparición completa de los radios presentes en cada aleta), lo que se observa a los 6.9 mm SL. La pigmentación externa en C. poeyi esta marcada por dos tendencias en el crecimiento: (1) un descenso en la pigmentación dorsal; y (2) un incremento en la pigmentación ventral a lo largo de la línea media. El desarrollo del viscerocráneo comienza con el aparecimiento del maxilar y el dentario en individuos de 2.4 mm NL, lo cual coincide con el consumo del saco vitelino. A los 10.6 mm SL todos los huesos del viscerocráneo están presentes como se observa en los dientes en los adultos. Algunos aspectos del desarrollo temprano en C. poeyi son comparados con los congéneros C. undecimalis y C. parallelus.(AU)


Asunto(s)
Animales , Ontología de Genes , Larva/crecimiento & desarrollo , Perciformes/crecimiento & desarrollo , Acuicultura
13.
Tijdschr Psychiatr ; 59(7): 414-421, 2017.
Artículo en Holandés | MEDLINE | ID: mdl-28703261

RESUMEN

BACKGROUND: Up till now, the experiences of people recovering from psychotic states and particularly from negative symptoms have scarcely been integrated into current scientific knowledge of recovery.
AIM: To contribute to the integration of scientific knowledge about recovery processes by creating an up-to-date model of negative symptoms.
METHOD: In our article we report the views and comments of an expert patient and a psychiatrist regarding crucial aspects of the recovery process of the patient who had experienced a long period of passivity.
RESULTS: Recovery seems to be aided by a number of 'soft' factors. The damage caused by the interruption in a patient's life-line has to be limited as far as possible. Patients must be given the opportunity to adjust to the new situation in which they find themselves. We describe various ways of encouraging interaction and exploration. Patients need to be presented with relevant samples of recovery so that they become optimistic about future improvements in their own mental health.
CONCLUSION: The approach outlined in this article is likely to contribute to a better understanding of this precarious mental health state.


Asunto(s)
Apatía , Trastornos Psicóticos/psicología , Asunción de Riesgos , Actitud , Humanos , Salud Mental
14.
J Morphol ; 278(6): 750-767, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28370364

RESUMEN

Miniaturization, the evolution of extremely small adult body size, is widespread amongst animals and commonly associated with novel ecological, physiological, and morphological attributes. The phenotypes of miniaturized taxa are noteworthy because they combine reductions and structural simplifications with novel traits not developed in their larger relatives. Previous research on miniature cyprinid fishes (focused predominantly on South and South East Asian taxa of a single subfamily) has identified two distinct classes of miniature taxa: proportioned dwarves and developmentally truncated miniatures. Miniaturization has also occurred independently in the subfamily Cyprininae, particularly in African lineages. We investigate the skeletal anatomy of Barboides, a genus of miniature African cyprinids that includes Africa's smallest known species of vertebrates, to assess whether miniaturization has resulted in similar organismal outcomes in different lineages of the Cyprinidae. The skeleton of Barboides is characterized by the complete absence of a number of dermal and endochondral ossifications, and marked reduction in size and/or complexity of other skeletal elements, particularly those of the dermatocranium. Absent skeletal elements in Barboides include those which develop relatively late in the ossification sequence of the non-miniature African relative 'Barbus' holotaenia suggesting that their absence in Barboides can be explained by a simple scenario of developmental truncation. In contrast to this theme of loss and reduction, the os suspensorium of Barboides is enlarged and the outer arm distally trifid and associated with a novel bulbous muscle in males. An evaluation of the skeleton of Barboides provides further evidence for a link between developmental truncation and evolutionary morphological novelty in Cyprinidae. In the spectrum of miniature cyprinids ranging from proportioned dwarves with few bones missing to highly progenetic taxa with dozens of missing bones, the two species of Barboides range roughly in the middle showing that the extremes are connected by intermediate levels of truncatedness.


Asunto(s)
Tamaño Corporal , Cyprinidae/anatomía & histología , Cyprinidae/crecimiento & desarrollo , África , Aletas de Animales/anatomía & histología , Estructuras Animales/anatomía & histología , Animales , Huesos/anatomía & histología , Región Branquial/anatomía & histología , Femenino , Masculino , Cráneo/anatomía & histología
15.
Lett Appl Microbiol ; 45(6): 635-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17908228

RESUMEN

AIMS: To further improve the soy-based medium, devoid of animal and dairy products, for a production of tetanus toxin by nutritional studies and to scale-up the Clostridium tetani process into small fermentors. METHODS AND RESULTS: Optimum production of tetanus toxin did not require addition of pantothenic acid, thiamine, riboflavin, pyridoxine, biotin and uracil, growth factors used by previous investigators. Furthermore, l-tyrosine and l-cysteine could be eliminated from our soy-based medium without effect. Seven carbon sources were compared with glucose in the soy-based medium, but none was found to be superior to glucose. The process was successfully scaled-up into 250-ml bottles, 1-l bottles and 1-l fermentors. CONCLUSIONS: Quite remarkably, when comparing the tetanus production process in our soy-based medium with the traditional animal/dairy-containing media, our medium does not require addition of expensive vitamins, uracil or carbon sources other than glucose. Furthermore, the l-tyrosine and l-cysteine components could be eliminated, making the medium (Hy-Soy, glucose, powdered iron and inorganic salts) much more simple and economical. The successful scale-up from test tubes into 1-l fermentors allows us to predict that further scale-up into large fermentors will be successful. SIGNIFICANCE AND IMPACT OF THE STUDY: Toxoid preparations made from toxin produced with animal and dairy products can contain undesirable contaminants such as the prion causing bovine spongiform encephalopathy (BSE; mad cow's disease) or antigenic peptides that stimulate anaphylactic reactions and other undesirable immune reactions in immunized hosts. Our vegetable-based process avoids such unfortunate possibilities. The medium, having been made simpler and less expensive, and shown to be scaleable from test tubes into small fermentors, should be excellent for large scale production of tetanus toxin.


Asunto(s)
Clostridium tetani/metabolismo , Medio de Cultivo Libre de Suero/química , Microbiología Industrial/métodos , Toxina Tetánica/biosíntesis , Metabolismo de los Hidratos de Carbono , Clostridium tetani/crecimiento & desarrollo , Medio de Cultivo Libre de Suero/economía , Compuestos Inorgánicos/metabolismo , Hierro/metabolismo , Sales (Química)/metabolismo , Proteínas de Soja/metabolismo
16.
Neuroscience ; 125(2): 337-47, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15062977

RESUMEN

The negative impact of chronic stress at the structure of apical dendrite branches of cornu ammonis 3 (CA3) pyramidal neurons is well established. However, there is no information available on the CA3 dendritic organization related to short-lasting stress, which suffices to produce long-term habituation or sensitization of anxiety behaviors and neuroendocrine responses. Here, we tested the effects evoked by brief stress on the arrangements of CA3 pyramidal neuron dendrites, and the activity-dependent properties of the commissural-associational (C/A) excitatory postsynaptic potentials (EPSPs). Adult male rats were socially defeated followed by 3 weeks without further treatment or as comparison exposed to a regimen of a social defeat every second day for the same time period. We assessed CA3 pyramidal neurons with somatic whole-cell recording and neurobiotin application in acute hippocampal slices. The results from morphometric analysis of post hoc reconstructions demonstrated that CA3 dendrites from repeatedly stressed rats were reduced in surface area and length selectively at the apical cone (70% of control, approximately 280 microm from the soma). Brief stress, however, produced a similar decrease in apical dendritic length (77% of control, approximately 400 microm from the soma), accompanied by an increased length (167% of control) and branch complexity at the basal cone. The structural changes of the dendrites significantly influenced signal propagation by shortening the onset latency of EPSPs and increasing input resistance (r=0.45, P<0.01), of which the first was significantly changed in repeatedly stressed animals. Both brief and repeated stress long-lastingly impaired long-term potentiation of C/A synapses to a similar degree (P<0.05). These data indicate that the geometric plasticity of CA3 dendrites is dissociated from repetition of aversive experiences. A double social conflict suffices to drive a dynamic reorganization, by site-selective elimination and de novo growth of dendrite branches over the course of weeks after the actual experience.


Asunto(s)
Dendritas/fisiología , Hipocampo/patología , Células Piramidales/fisiopatología , Estrés Psicológico/fisiopatología , Glándulas Suprarrenales , Animales , Peso Corporal/fisiología , Tamaño de la Célula , Estimulación Eléctrica/métodos , Electrofisiología/métodos , Potenciales Postsinápticos Excitadores/fisiología , Hipocampo/efectos de la radiación , Técnicas In Vitro , Potenciación a Largo Plazo/fisiología , Masculino , Potenciales de la Membrana/fisiología , Plasticidad Neuronal , Tamaño de los Órganos/fisiología , Células Piramidales/efectos de la radiación , Ratas , Ratas Wistar , Factores de Tiempo
17.
FASEB J ; 15(14): 2689-701, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11726545

RESUMEN

Differential display of hippocampal tissue after entorhinal cortex lesion (ECL) revealed decreases in mRNA encoding the neuronal hyperpolarization-activated, cyclic nucleotide-gated channel HCN1. In situ hybridization confirmed that hippocampal transcripts of HCN1, but not HCN2/3/4, are down-regulated after ECL. Expression recovered at approximately 21 days after lesion (dal). Immunohistochemistry demonstrated a corresponding regulation of HCN1 protein expression in CA1-CA3 dendrites, hilar mossy cells and interneurons, and granule cells. Patch-clamp recordings in the early phase after lesion from mossy cells and hilar interneurons revealed an increase in the fast time constant of current activation and a profound negative shift in voltage activation of Ih. Whereas current activation recovered at 30 dal, the voltage activation remained hyperpolarized in mossy cells and hilar interneurons. Granule cells, however, were devoid of any detectable somatic Ih currents. Hence, denervation of the hippocampus decreases HCN1 and concomitantly the Ih activity in hilar neurons, and the recovery of h-current activation kinetics occurs parallel to postlesion sprouting.


Asunto(s)
Corteza Entorrinal/fisiopatología , Hipocampo/fisiología , Canales Iónicos/fisiología , Animales , Canales Catiónicos Regulados por Nucleótidos Cíclicos , Giro Dentado/citología , Giro Dentado/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/citología , Hipocampo/metabolismo , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización , Hibridación in Situ , Canales Iónicos/genética , Ácido Kaínico/farmacología , Masculino , Potenciales de la Membrana/fisiología , Microscopía Electrónica , Neuronas/citología , Neuronas/metabolismo , Neuronas/ultraestructura , Canales de Potasio , ARN/genética , ARN/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
18.
Neurosci Lett ; 307(1): 53-6, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11516573

RESUMEN

This study tested the time-of-day dependence of the intrinsic postsynaptic properties of hippocampal CA3 pyramidal neurons. High-voltage-activated Ca2+ currents and the Ca(2+)- and voltage-dependent afterhyperpolarizations were examined in slices of rat brains obtained at four distinct time periods. Just after onset of the dark phase, the steady-state amplitude of the Ca2+ current (-1.24+/-0.11 nA) was significantly greater (P<0.03) than that of the light phase (-0.84+/-0.06 nA). Over the entire time range, the amplitude of the Ca2+ current correlated with plasma corticosterone levels in a U-shaped function. Furthermore, depolarization-induced excitability during the dark phase exhibited an increased spike after depolarization (3.1+/-0.1 mV) and a slower adaptation of the firing frequency (146+/-18%). These findings point to a dynamic time-of-day dependence of the CA3 neuronal properties and postsynaptic Ca2+ currents.


Asunto(s)
Potenciales de Acción/fisiología , Canales de Calcio/metabolismo , Ritmo Circadiano/fisiología , Corticosterona/sangre , Hipocampo/metabolismo , Células Piramidales/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Cadmio/farmacología , Canales de Calcio/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Corticosterona/farmacología , Hipocampo/citología , Hipocampo/efectos de los fármacos , Masculino , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Técnicas de Placa-Clamp , Células Piramidales/citología , Células Piramidales/efectos de los fármacos , Ratas , Ratas Wistar
19.
Neurosurgery ; 48(2): 412-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11220387

RESUMEN

The Henry Ford Hospital (HFH) was founded in 1915 as a philanthropic gift from Henry Ford, the automobile magnate and inventor of the Model T. The hospital and its organizational structure represented a nonsectarian facility that would provide care for all members of society. The system was patterned after the newest and most modern medical centers at the time in Europe, Canada, and the United States, including the German Krankenhauser, the Johns Hopkins Hospital, the Mayo Clinic, and the Peter Bent Brigham Hospital in Boston. The HFH grew into the Henry Ford Health System in the 1970s to 1990s, with the acquisition of other hospitals, the development of a multiple-region-based clinic system through southeastern Michigan, and the development of comprehensive, vertically integrated health care systems. The Division of Neurosurgery at HFH was established by Albert Crawford in 1926. The tradition of training residents in neurosurgery began in 1946, and the residency training program was accredited by the American Board of Neurosurgery in 1954. In 1970, the Division of Neurosurgery of the Department of Surgery was combined with the Division of Neurology to create the joint Department of Neurology and Neurosurgery. A separate Department of Neurosurgery was established in 1981. Four individuals have served as chairmen of the Department of Neurosurgery at HFH, i.e., Albert Crawford (1926-1952), Robert Knighton (1952-1978), James Ausman (1978-1991), and Mark Rosenblum (1992 to the present). During the 1980s and 1990s, HFH evolved into the vertically integrated, regionally distributed Henry Ford Health System. Under the current direction of Dr. Rosenblum, the Department of Neurosurgery at HFH has grown to include 11 full-time neurosurgeons, 2 neuro-oncologists, and 3 investigators with Ph.D. degrees and has recently expanded into three additional hospitals in southeastern Michigan, paralleling the growth of the system. The faculty annually treats more than 2,000 cases in all neurosurgical subspecialties, ranging from neuro-oncological surgery, cranial base surgery, radiosurgery, cerebrovascular surgery, epilepsy surgery, treatment of movement disorders, pain and spasticity surgery, pediatric neurosurgery, and neurotrauma treatment to complex instrumentation of the spine. This article chronicles the history of the Henry Ford Health System and the Department of Neurosurgery, its research endeavors, and its residency training program.


Asunto(s)
Hospitales Urbanos/historia , Neurocirugia/historia , Servicio de Cirugía en Hospital/historia , Atención a la Salud/historia , Personajes , Historia del Siglo XX , Humanos , Industrias/historia , Michigan , Servicio de Cirugía en Hospital/organización & administración
20.
Biochem Eng J ; 7(2): 153-156, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11173304

RESUMEN

A new mixing probe has been developed which measures the motions of the fluid during mixing as pressure fluctuations and converts the measurements into a mixing signal (MS). The MS is the root mean square (RMS) pressure fluctuation in the 1-64Hz range as determined by a sensitive pressure sensor and a digital signal processor specifically designed for the purpose. The MS is a measure of the actual mixing flow of the fluid rather than a measurement of the input motions or energies into the reactor system (e.g. RPM, torque or power). In other studies, the MS has been measured as a function of mixing speed in numerous sized reactors from 10 to 1000l, and provides consistent and reproducible measurements. The MS increases monotonically as a function of mixing speed, with a change of slope corresponding to the transition from laminar to turbulent mixing regimes. Maps of MS as a function of location in the reactor are useful in understanding stirred tank reactor design and performance. Quantitative measurements of mixing are especially useful during process development as a tool to increase the success of scale-up during the transition from process development to manufacturing. Measurements at a fixed location in a given reactor are useful in understanding changes in mixing that occur during the course of a given process, and are useful in manufacturing situations where validated documentation of lot-to-lot consistency of mixing is required (e.g. pharmaceutical manufacturing). In addition, the probe has been used to measure mixing in vessels with vibrational mixers with similar results. The probe has been successfully used in feedback loops to control either mixing speed or vibrational mixing amplitude in order to maintain constant mixing of the fluid during processing. With this system it is possible to maintain constant mixing over a wide range of fluid volumes in a given reactor, and, for instance, to compensate for changes in viscosity throughout the course of the process. Adaptations of this system for the measurement of mixing in shake-flasks is described in this paper.

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