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1.
J Pain ; 25(2): 331-349, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37673193

RESUMO

Persistent pain conditions and sleep disorders are public health problems worldwide. It is widely accepted that sleep disruption increases pain sensitivity; however, the underlying mechanisms are poorly understood. In this study, we used a protocol of 6 hours a day of total sleep deprivation for 3 days in rats to advance the understanding of these mechanisms. We focused on gender differences and the dopaminergic mesocorticolimbic system. The findings demonstrated that sleep restriction (SR) increased pain sensitivity in a similar way in males and females, without inducing a significant stress response. This pronociceptive effect depends on a nucleus accumbens (NAc) neuronal ensemble recruited during SR and on the integrity of the anterior cingulate cortex (ACC). Data on indirect dopaminergic parameters, dopamine transporter glycosylation, and dopamine and cyclic adenosine monophosphate (AMP)-regulated phosphoprotein-32 phosphorylation, as well as dopamine, serotonin, and norepinephrine levels, suggest that dopaminergic function decreases in the NAc and ACC after SR. Complementarily, pharmacological activation of dopamine D2, but not D1 receptors either in the ACC or in the NAc prevents SR from increasing pain sensitivity. The ACC and NAc are the main targets of dopaminergic mesocorticolimbic projections with a key role in pain modulation. This study showed their integrative role in the pronociceptive effect of SR, pointing to dopamine D2 receptors as a potential target for pain management in patients with sleep disorders. These findings narrow the focus of future studies on the mechanisms by which sleep impairment increases pain sensitivity. PERSPECTIVE: This study demonstrates that the pronociceptive effect of SR affects similarly males and females and depends on a NAc neuronal ensemble recruited during SR and on the integrity of the ACC. Findings on dopaminergic function support dopamine D2 receptors as targets for pain management in sleep disorders patients.


Assuntos
Dopamina , Núcleo Accumbens , Humanos , Masculino , Ratos , Animais , Núcleo Accumbens/fisiologia , Dopamina/farmacologia , Giro do Cíngulo , Dor , Privação do Sono/complicações
4.
Br J Oral Maxillofac Surg ; 59(1): e23-e26, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33131803

RESUMO

Head and neck cancer (HNC) is the 7th most prevalent cancer globally, with an increasing incidence in recent years which is expected to continue. For many patients, the experience of receiving a diagnosis of HNC and subsequent treatment is disturbing and traumatic. Evidence suggests that HNC patients have a significantly increased risk of suicide compared with other cancer patients and the general population. Multiple social and medical factors may increase suicide risk in an individual, and include smoking and alcohol misuse. Given the elevated rate of suicide among HNC patients it is prudent to routinely assess patients for suicidal ideation to prevent unnecessary deaths by suicide. However, to the authors' knowledge, such assessments are not undertaken in most centres. This article describes the development of a suicide risk assessment protocol proposed for use in HNC patients in a major University Teaching Hospital in Leeds. The basic structure of this protocol could easily be adopted to other centres.


Assuntos
Neoplasias de Cabeça e Pescoço , Suicídio , Humanos , Fatores de Risco , Ideação Suicida , Fumar Tabaco
5.
Theriogenology ; 158: 490-496, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33080452

RESUMO

An experiment was designed to evaluate the effectiveness of the recently developed 7 & 7 Synch protocol to synchronize estrus among recipients prior to embryo transfer (ET). Postpartum beef cows (n = 1358) across thirteen locations were assigned to either the 7-d CO-Synch + CIDR protocol or the 7 & 7 Synch protocol prior to ET. Cows were preassigned to balanced treatments within location based on age and days postpartum, with body condition score recorded at ET. Cows assigned to the 7-d CO-Synch + CIDR protocol were administered gonadotropin-releasing hormone (GnRH; 100 µg gonadorelin acetate) on Day 7, an intravaginal controlled internal drug release (CIDR; 1.38 g progesterone) from Day 7 to Day 14, and prostaglandin F2α (PGF2α; 25 mg dinoprost tromethamine) coincident with CIDR removal on Day 14. Cows assigned to the 7 & 7 Synch protocol were administered PGF2α (25 mg dinoprost tromethamine) coincident with CIDR insertion on Day 0, GnRH (100 µg gonadorelin acetate) on Day 7, and PGF2α (25 mg dinoprost tromethamine) coincident with CIDR removal on Day 14. Cows were observed for visible signs of estrus, with GnRH (100 µg gonadorelin acetate) administered to cows failing to express estrus during the detection period. Embryo transfer was performed approximately seven days after estrus or GnRH administration. Presence of corpora lutea (CL) was determined via transrectal palpation by a single veterinarian blinded to treatment, and embryos were transferred only to cows with palpable CL. Embryo transfer was performed using either fresh or frozen embryos, with embryo stage and grade recorded for each recipient. The proportion of cows expressing estrus was increased (P < 0.0001) among cows assigned to the 7 & 7 Synch protocol (86% [529/615] vs 76% [488/640]). The proportion of cows expressing estrus and presenting with palpable CL at ET was greater (P < 0.0001) among cows following treatment with the 7 & 7 Synch protocol compared to the 7-d CO-Synch + CIDR protocol (76% [466/615] vs 65% [418/640]). Consequently, the proportion pregnant to ET was greater (P < 0.03) following the 7 & 7 Synch protocol (40% [263/653]) compared to the 7-d CO-Synch + CIDR protocol (34% [228/664]). In summary, the 7 & 7 Synch protocol involving administration of PGF2α and treatment with a CIDR for 7 days prior to GnRH improved the likelihood of estrus expression in recipients, increased the proportion of cows eligible to receive an embryo, which resulted in a greater pregnancy rate to ET.


Assuntos
Sincronização do Estro , Inseminação Artificial , Animais , Bovinos , Dinoprosta/farmacologia , Transferência Embrionária/veterinária , Detecção do Estro , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/veterinária , Gravidez , Progesterona
6.
Br J Oral Maxillofac Surg ; 58(9): e6-e15, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32682651

RESUMO

The treatment of head and neck cancer (HNC) is often radical and the patient's journey challenging, especially for individuals who are struggling with pre-existing mental health problems and who lack social support. Patients frequently suffer from high levels of emotional distress at some point before, during, or after treatment, and their risk of suicide is markedly elevated. This structured review aimed to identify the extent of the problem, appropriate interventions, and areas for future research. We found that the incidence of suicide among HNC patients was significantly elevated above that of the demographically matched general population. Furthermore, the risk was frequently higher in patients with HNC than in those with cancers in other sites. Despite the clear burden of suicide in patients with HNC, there is an absence of evidence on interventions used to reduce suicidal ideation and the risk of suicide. Recommendations for practice are made, drawing from the wider literature on the prevention of suicide.


Assuntos
Neoplasias de Cabeça e Pescoço , Prevenção do Suicídio , Humanos , Incidência , Fatores de Risco , Ideação Suicida
7.
Bone Rep ; 12: 100250, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32090156

RESUMO

PURPOSE: The classic fracture model, described by Bonnarens and Einhorn in 1984, enlists a blunt guillotine to generate a closed fracture in a pre-stabilized rodent femur. However, in less experienced hands, this technique yields considerable variability in fracture pattern and requires highly-specialized equipment. This study describes a reproducible and low-cost model of mouse fracture healing using an open femoral osteotomy. METHODS: Femur fractures were produced in skeletally mature male and female mice using an open femoral osteotomy after intramedullary stabilization. Mice were recovered for up to 28 days prior to analysis with microradiographs, histomorphometry, a novel µCT methodology, and biomechanical torsion testing at weekly intervals. RESULTS: Eight mice were excluded due to complications (8/193, 4.1%), including unacceptable fracture pattern (2/193, 1.0%). Microradiographs showed progression of the fracture site to mineralized callus by 14 days and remodelling 28 days after surgery. Histomorphometry from 14 to 28 days revealed decreased cartilage area and maintained bone area. µCT analysis demonstrated a reduction in mineral surface from 14 to 28 days, stable mineral volume, decreased strut number, and increased strut thickness. Torsion testing at 21 days showed that fractured femurs had 61% of the ultimate torque, 63% of the stiffness, and similar twist to failure when compared to unfractured contralateral femurs. CONCLUSIONS: The fracture model described herein, an open femoral osteotomy, demonstrated healing comparable to that reported using closed techniques. This simple model could be used in future research with improved reliability and reduced costs compared to the current options.

8.
Sci Rep ; 9(1): 16976, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740683

RESUMO

High-fidelity single-shot readout of spin qubits requires distinguishing states much faster than the T1 time of the spin state. One approach to improving readout fidelity and bandwidth (BW) is cryogenic amplification, where the signal from the qubit is amplified before noise sources are introduced and room-temperature amplifiers can operate at lower gain and higher BW. We compare the performance of two cryogenic amplification circuits: a current-biased heterojunction bipolar transistor circuit (CB-HBT), and an AC-coupled HBT circuit (AC-HBT). Both circuits are mounted on the mixing-chamber stage of a dilution refrigerator and are connected to silicon metal oxide semiconductor (Si-MOS) quantum dot devices on a printed circuit board (PCB). The power dissipated by the CB-HBT ranges from 0.1 to 1 µW whereas the power of the AC-HBT ranges from 1 to 20 µW. Referred to the input, the noise spectral density is low for both circuits, in the 15 to 30 fA/[Formula: see text] range. The charge sensitivity for the CB-HBT and AC-HBT is 330 µe/[Formula: see text] and 400 µe/[Formula: see text], respectively. For the single-shot readout performed, less than 10 µs is required for both circuits to achieve bit error rates below 10-3, which is a putative threshold for quantum error correction.

9.
Conserv Physiol ; 7(1): coz011, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110763

RESUMO

A strength of physiological ecology is its incorporation of aspects of both species' ecology and physiology; this holistic approach is needed to address current and future anthropogenic stressors affecting elasmobranch fishes that range from overexploitation to the effects of climate change. For example, physiology is one of several key determinants of an organism's ecological niche (along with evolutionary constraints and ecological interactions). The fundamental role of physiology in niche determination led to the development of the field of physiological ecology. This approach considers physiological mechanisms in the context of the environment to understand mechanistic variations that beget ecological trends. Physiological ecology, as an integrative discipline, has recently experienced a resurgence with respect to conservation applications, largely in conjunction with technological advances that extended physiological work from the lab into the natural world. This is of critical importance for species such as elasmobranchs (sharks, skates and rays), which are an especially understudied and threatened group of vertebrates. In 2017, at the American Elasmobranch Society meeting in Austin, Texas, the symposium entitled `Applications of Physiological Ecology in Elasmobranch Research' provided a platform for researchers to showcase work in which ecological questions were examined through a physiological lens. Here, we highlight the research presented at this symposium, which emphasized the strength of linking physiological tools with ecological questions. We also demonstrate the applicability of using physiological ecology research as a method to approach conservation issues, and advocate for a more available framework whereby results are more easily accessible for their implementation into management practices.

10.
Scand J Med Sci Sports ; 27(1): 66-74, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26643874

RESUMO

Stress-inducible Hsp72 is a potential biomarker to track risk of exertional heat illness during exercise/environmental stress. Characterization of extracellular (eHsp72) vs cellular Hsp72 (iHsp72) responses is required to define the appropriate use of Hsp72 as a reliable biomarker. In each of four repeat visits, participants (n = 6 men, 4 trials; total n = 24): (a) passively dehydrated overnight, (b) exercised (2 h) with no fluid in a hot, humid environmental chamber, (c) rested and rehydrated (1 h), (d) maximally exercised for 0.5 h, and (e) returned after 24 h of at-home recovery and rehydration. We measured rectal temperature, hydration status (% body mass loss, urine markers, serum osmolality), and Hsp72 (ELISA, flow cytometry. eHsp72 (circulating) and iHsp72 (CD3+ PBMCs) correlated (P < 0.05) with markers of heat, exercise, and dehydration stresses. eHsp72 immediately post-exercise (>15% above baseline, P < 0.05) decreased back to baseline levels by 1 h post-exercise, but iHsp72 expression continued to rise and remained elevated 24 h post-exercise (~2.5-fold baseline, P < 0.05). These data suggest that in addition to the classic physiological biomarkers of exercise heat stress, using cellular Hsp72 as an indicator of lasting effects of stress into recovery may be most appropriate for determining long-term effects of stress on risk for exertional heat illness.


Assuntos
Temperatura Corporal , Desidratação/metabolismo , Exercício Físico/fisiologia , Proteínas de Choque Térmico HSP72/metabolismo , Transtornos de Estresse por Calor/metabolismo , Temperatura Alta , Umidade , Estresse Fisiológico/fisiologia , Adulto , Biomarcadores/metabolismo , Espaço Extracelular/metabolismo , Humanos , Masculino , Concentração Osmolar , Distribuição Aleatória , Adulto Jovem
11.
Phys Rev Lett ; 114(16): 165001, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25955053

RESUMO

We present measurements of radio emission from cosmic ray air showers that took place during thunderstorms. The intensity and polarization patterns of these air showers are radically different from those measured during fair-weather conditions. With the use of a simple two-layer model for the atmospheric electric field, these patterns can be well reproduced by state-of-the-art simulation codes. This in turn provides a novel way to study atmospheric electric fields.

12.
Hernia ; 19(4): 645-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24728835

RESUMO

PURPOSE: Losartan, a commonly used angiotensin II receptor blocker (ARB) for blood pressure control, also impairs cutaneous wound healing. Our current study will analyze how Losartan affects wound healing in the muscle and fascia from both biomechanical and histological aspects. METHODS: A total of 26 Sprague-Dawley rats were separated into one control group (NS, N = 13) and one experimental group (LG, N = 13) to receive normal saline and 40 mg/kg of Losartan by way of gastric lavage, respectively. 7 days later, all animals were subjected to a 5 cm midline laparotomy. The fascia and skin were then closed with 4-0 prolene and 5-0 vicryl. 15 days postoperatively, the animals were sacrificed and the abdominal wall harvested for wound tensiometric test and histological analysis. RESULTS: All 26 rats survived to the time of necropsy. Tensiometry detected significantly higher wound tensile strength in the NS group (1.6 ± 0.31 N/mm) than in the LG (1.3 ± 0.28 N/mm) group (p = 0.016). Transection histology with trichrome staining demonstrated higher degree of immature fibroplasia inside the wound in the LG group than in the NS group (p = <0.0001). The LG group also had larger incisional gaps than the NG group. CONCLUSION: The antihypertensive drug, Losartan, retards wound healing in the abdominal fascia and reduces wound tensile strength in our rat model. Attention should be paid to the potential effects of various medications on fascial wound healing to guarantee optimal surgical outcomes.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Fáscia/efeitos dos fármacos , Losartan/efeitos adversos , Cicatrização/efeitos dos fármacos , Músculos Abdominais/efeitos dos fármacos , Parede Abdominal/cirurgia , Animais , Modelos Animais de Doenças , Fasciotomia , Laparotomia , Masculino , Ratos , Ratos Sprague-Dawley , Resistência à Tração/efeitos dos fármacos , Cicatrização/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-33898111

RESUMO

This paper reports long-term evaluation of a micropackage technology for an implantable MEMS pressure sensor. The all-polymer micropackage survived 160 days when subjected to accelerated lifetime testing at 85 °C in a 1% wt. saline solution. The package shows minimum effect on sensors' sensitivity and nonlinearity, which deviated by less than 5% and 0.3%, respectively. A 6-month in vivo evaluation of 16 MEMS-based pressure sensors demonstrated that the proposed micropackage has good biocompatibility and can protect the MEMS pressure sensor. To the best of our knowledge, these results establish new lifetime records for devices packaged using an all-polymer micropackaging approach.

14.
J Pharmacol Toxicol Methods ; 67(3): 140-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23376811

RESUMO

INTRODUCTION: The conversion from intravenous (IV) to subcutaneous (SC) delivery of biotherapeutics has increased in recent years. Some of the reasons for this shift in route of delivery are due to patient convenience, reduced adverse systemic effects, lack of a need for vascular access, and reduced cost of patient care, which ultimately lead to improved patient quality of life. One caveat to SC delivery is the limited volumes that can be administered at a single site and the associated local tolerability. To characterize factors that affect subcutaneous delivery of large volumes of therapeutic proteins, a porcine model was developed. Model endpoints included measurement of interstitial pressure, assessment of local skin visco-elasticity, and the qualitative assessment of local infusion sites. METHODS: Immunoglobulin G (IgG) was subcutaneously infused into the abdominal region of Yucatan miniature swine. Changes in interstitial pressure were measured, using an in-line pressure transducer, during and after infusions. Additionally, pre- and post-infusion changes in local skin visco-elasticity were measured using a Cutometer®. Lastly, infusion sites were assessed for post-infusion local skin reactions such as erythema and swelling. Similar assessments were made following SC IgG delivery with the permeation enhancer recombinant human hyaluronidase PH20 (rHuPH20). RESULTS: Subcutaneous infusions of IgG, in the presence of rHuPH20, significantly reduced average interstitial pressures by 55% during the infusion period and by 67% during the post-infusion period, compared to the control. Infusions in the presence of rHuPH20 also maintained better local skin elasticity as seen by a 42% increase in local skin pliability compared to the control. Finally, infusions with rHuPH20 resulted in an 80% reduction in swelling area compared to the control. DISCUSSION: A large animal model was developed that incorporates both quantitative and qualitative assessment methods to aid in understanding SC delivery of proteins.


Assuntos
Imunoglobulina G/administração & dosagem , Imunoglobulina G/toxicidade , Modelos Animais , Pele/efeitos dos fármacos , Tela Subcutânea/efeitos dos fármacos , Abdome , Animais , Moléculas de Adesão Celular/administração & dosagem , Humanos , Hialuronoglucosaminidase/administração & dosagem , Infusões Subcutâneas , Proteínas Recombinantes/administração & dosagem , Suínos
16.
Lab Anim ; 45(3): 131-40, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21478271

RESUMO

Streptozotocin (STZ)-induced diabetes mellitus (DM) offers a very cost-effective and expeditious technique that can be used in most strains of rodents, opening the field of DM research to an array of genotypic and phenotypic options that would otherwise be inaccessible. Despite widespread use of STZ in small animal models, the data available concerning drug preparation, dosing and administration, time to onset and severity of DM, and any resulting moribundity and mortality are often limited and inconsistent. Because of this, investigators inexperienced with STZ-induced diabetes may find it difficult to precisely design new studies with this potentially toxic chemical and account for the severity of DM it is capable of inducing. Until a better option becomes available, attempts need to be made to address shortcomings with current STZ-induced DM models. In this paper we review the literature and provide data from our pancreatic islet transplantation experiments using single high-dose STZ-induced DM in NCr athymic nude mice with hopes of providing clarification for study design, suggesting refinements to the process, and developing a more humane process of chemical diabetes induction.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/efeitos dos fármacos , Estreptozocina/farmacologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/mortalidade , Diabetes Mellitus Experimental/fisiopatologia , Feminino , Transplante das Ilhotas Pancreáticas/mortalidade , Masculino , Camundongos , Camundongos Nus , Projetos de Pesquisa , Fatores Sexuais , Estreptozocina/administração & dosagem
17.
Cell Death Differ ; 18(5): 907-13, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21212797

RESUMO

Neuronal differentiation from expanded human ventral mesencephalic neural precursor cells (NPCs) is very limited. Astrocytes are known to secrete neurotrophic factors, and so in order to enhance neuronal survival from NPCs, we tested the effect of regional astrocyte-conditioned medium (ACM) from the rat cortex, hippocampus and midbrain on this process. Human NPC's were expanded in FGF-2 before differentiation for 1 or 4 weeks in ACM. The results show that ACM from the hippocampus and midbrain increase the number of neurons from expanded human NPCs, an effect that was not observed with cortical ACM. In addition, both hippocampal and midbrain ACM increased the number and length of phosphorylated neurofilaments. MALDI-TOF analysis used to determine differences in media revealed that although all three regional ACMs had cystatin C, α-2 macroglobulin, extracellular matrix glycoprotein and vimentin, only hippocampal and midbrain ACM also contained clusterin, which when immunodepleted from midbrain ACM eliminated the observed effects on neuronal differentiation. Furthermore, clusterin is a highly glycosylated protein that has no effect on cell proliferation but decreases apoptotic nuclei and causes a sustained increase in phosphorylated extracellular signal-regulated kinase, implicating its role in cell survival and differentiation. These findings further reveal differential effects of regional astrocytes on NPC behavior and identify clusterin as an important mediator of NPC-derived neuronal survival and differentiation.


Assuntos
Astrócitos/metabolismo , Diferenciação Celular , Clusterina/metabolismo , Células-Tronco Neurais/citologia , Neurônios/citologia , Animais , Sobrevivência Celular , Células Cultivadas , Córtex Cerebral/citologia , Clusterina/farmacologia , Meios de Cultivo Condicionados , Cistatina C/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Hipocampo/citologia , Humanos , Mesencéfalo/citologia , Proteínas de Neurofilamentos/metabolismo , Neurônios/metabolismo , Fosforilação , Ratos , Tubulina (Proteína)/metabolismo , Vimentina/metabolismo , alfa-Macroglobulinas/metabolismo
18.
Toxicology ; 276(3): 198-205, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-20708649

RESUMO

Triphenyltin (TPT) is an organotin compound (OTC) previously widely used as an antifouling agent in paints applied in the marine environment, a fungicide, and as an agricultural pesticide. In female aquatic invertebrates, certain OTCs induce the so-called imposex, an abnormal induction of male sex characteristics. OTC-induced environmental endocrine disruption also occurs in fish and mammals and a number of in vivo and in vitro studies have argued that OTCs may act through inhibition of the aromatase enzyme. In vivo studies supporting the aromatase inhibition hypothesis in mammals are lacking. Recently, the causal relationship between inhibition of aromatase and imposex was questioned, suggesting aromatase independent mechanisms of action for this phenomenon. We conducted a comprehensive investigation to identify the most sensitive window of exposure to TPTCl and to examine the effects of pre- and postnatal exposure on postnatal development in rats. The results on brain and gonadal aromatase activity obtained from offspring of dams exposed to 2 mg TPTCl/kg bw are reported here. Female and male offspring rats were exposed to 2 mg TPTCl/kg bw/d in utero from gestation day 6 through lactation until weaning on PND 21, or from gestation day 6 until termination at adulthood. Male offspring were sacrificed from PND 58 and female offspring at first estrus after PND 58. Pre- and postnatal TPT exposure clearly affected brain and gonadal aromatase activity in a sex-dependent fashion. While brain aromatase activity was significantly increased on PND 21 and at adulthood in female offspring, male offspring exhibited a significant decrease in brain aromatase activity only at adulthood. Ovarian aromatase activity was unaffected at both time points investigated. In contrast, testicular aromatase activity was significantly increased in males on PND 21 and significantly decreased at adulthood independent from the duration of treatment. The results of the present study confirm our previously reported observations regarding sex-dependent differences in sexual development after TPT exposure with the male rat being more susceptible to disturbances through this endocrine active compound than the female. We conclude that TPT administered during the particularly vulnerable period of development can affect aromatase activity in rats.


Assuntos
Aromatase/metabolismo , Disruptores Endócrinos/toxicidade , Compostos Orgânicos de Estanho/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/enzimologia , Caracteres Sexuais , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Disruptores Endócrinos/administração & dosagem , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Feminino , Gônadas/efeitos dos fármacos , Gônadas/enzimologia , Masculino , Compostos Orgânicos de Estanho/administração & dosagem , Gravidez , Ratos , Ratos Wistar
19.
Insect Mol Biol ; 19(2): 229-41, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20017753

RESUMO

Murine typhus is a flea-borne febrile illness that is caused by the obligate intracellular bacterium, Rickettsia typhi. The cat flea, Ctenocephalides felis, acquires R. typhi by imbibing a bloodmeal from a rickettsemic vertebrate host. To explore which transcripts are expressed in the midgut in response to challenge with R. typhi, cDNA libraries of R. typhi-infected and uninfected midguts of C. felis were constructed. In this study, we examined midgut transcript levels for select C. felis serine proteases, GTPases and defence response genes, all thought to be involved in the fleas response to feeding or infection. An increase in gene expression was observed for the serine protease inhibitors and vesicular trafficking proteins in response to feeding. In addition, R. typhi infection resulted in an increase in gene expression for the chymotrypsin and rab5 that we studied. Interestingly, R. typhi infection had little effect on expression of any of the defence response genes that we studied. We are unsure as to the physiological significance of these gene expression profiles and are currently investigating their potential roles as it pertains to R. typhi infection. To our knowledge, this is the first report of differential expression of flea transcripts in response to infection with R. typhi.


Assuntos
Interações Hospedeiro-Patógeno/genética , Rickettsia typhi/patogenicidade , Sifonápteros/genética , Sifonápteros/microbiologia , Tifo Endêmico Transmitido por Pulgas/genética , Tifo Endêmico Transmitido por Pulgas/microbiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Gatos , Primers do DNA/genética , Sistema Digestório/enzimologia , Sistema Digestório/microbiologia , Expressão Gênica , Biblioteca Gênica , Genes de Insetos , Insetos Vetores/genética , Insetos Vetores/microbiologia , Dados de Sequência Molecular , Peptídeo Hidrolases/genética , Homologia de Sequência de Aminoácidos , Sifonápteros/enzimologia , Transcrição Gênica
20.
Diabet Med ; 26(11): 1135-40, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19929992

RESUMO

AIM: There is little information about maternal central haemodynamics and arterial stiffness in pregnancies affected by Type 1 diabetes mellitus. The aim of the current study was to investigate whether maternal arterial stiffness is altered in pregnant women with Type 1 diabetes mellitus compared with women with uncomplicated pregnancies. METHODS: This was a cross-sectional study involving 37 pregnant women without diabetes and 37 pregnant women with Type 1 diabetes mellitus during the second trimester of pregnancy. Maternal wave reflection (augmentation index) and pulse wave velocity of the carotid-femoral and carotid-radial part of the arterial tree were assessed non-invasively using applanation tonometry. RESULTS: Pregnant women with normal pregnancies and Type 1 diabetes mellitus had similar augmentation index (3.7 +/- 12.8 vs. 5.1 +/- 12.6%, P = 0.6), even after adjusting for possible confounders. Within the group of diabetic women, augmentation index was associated with duration of diabetes (P = 0.003, r(2) = 0.22) but not with glycated haemoglobin. Pulse wave velocities were similar between the two groups of women (carotid-femoral: 5.6 +/- 0.9 vs. 5.7 +/- 1.1 m/s, P = 0.4; carotid-radial: 7.4 +/- 1.2 vs. 7.8 +/- 1 m/s, P = 0.1). In the diabetic women there was no significant association between the pulse wave velocities and either duration of diabetes or glycated haemoglobin. CONCLUSIONS: Pregnancy in women with Type 1 diabetes mellitus is not associated with altered maternal systemic arterial stiffness. However, maternal wave reflections increase with the duration of diabetes.


Assuntos
Artérias Carótidas/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Hemodinâmica/fisiologia , Complicações Cardiovasculares na Gravidez/fisiopatologia , Gravidez em Diabéticas , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Feminino , Humanos , Gravidez , Complicações Cardiovasculares na Gravidez/etiologia , Segundo Trimestre da Gravidez
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