Hepatitis C virus-positive donors in HCV-negative recipients in liver transplantation: Is it possible in Mexico?

Hepatitis C virus (HCV) infection is a worldwide public health problem associated with significant morbidity and mortality. In the context of liver transplantation, the demand for organs continues to exceed the supply, prompting the consideration of using organs from HCV-positive donors in HCV-negative recipients. The introduction of direct-acting antivirals (DAAs), which have demonstrated great efficacy in eradicating the virus, has made transplantation of organs from donors with HCV infection possible. The present article provides a brief review of the current evidence on the use of organs from HCV-infected patients.

Perfil de resistencia antibiótica en infecciones oculares en un centro de referencia en Floridablanca, Colombia / Antibiotic resistance profile in eye infections in a reference centre in Floridablanca, Colombia

Antecedentes y objetivo: Ante la creciente resistencia bacteriana a los antibióticos es necesario determinarla de manera local para servir de guía en el manejo clínico. El propósito de este estudio fue caracterizar el patrón de sensibilidad antibiótica en casos de infecciones oculares en una institución oftalmológica de tercer nivel en Floridablanca (Colombia). Materiales y métodos: Estudio observacional de corte transversal en el cual se analizaron los informes de cultivo y antibiograma de muestras tomadas de casos de conjuntivitis, queratitis infecciosas y endoftalmitis entre enero de 2013 y junio del 2016. Resultados: Ochocientas treinta y tres muestras fueron positivas para bacterias. Considerando microorganismos tanto grampositivos como gramnegativos, la gentamicina, la tobramicina y la ciprofloxacina mostraron tasas de resistencia altas (64,4; 40,3% y 29,1%). La moxifloxacina, la vancomicina, el imipenem y la gatifloxacina mostraron bajos porcentajes de resistencia: 2,6; 2,1; 0,6 y 0,4% respectivamente. Al comparar los resultados con estudios previos en nuestra institución se evidenció una disminución de la sensibilidad a las quinolonas de cuarta generación y al imipenem, especialmente dentro de los gramnegativos. Conclusión: Las quinolonas de cuarta generación, el imipenem y la vancomicina siguen teniendo in vitro una baja resistencia de las bacterias causantes de infecciones oculares. Sin embargo, se evidenció una tendencia al incremento de la resistencia de las bacterias gramnegativas. Se deben tomar medidas para intentar controlar este fenómeno, y pensar en posibles alternativas de terapia antimicrobiana ante infecciones causadas por estos microorganismos

Background and objective: In view of the increasing bacterial resistance to antibiotics, it is necessary to determine it locally in order to serve as a guide in clinical management. The purpose of this study was to characterise the pattern of antibiotic sensitivity in cases of eye infections in a third level ophthalmological institution in Floridablanca (Colombia). Materials and methods: An observational cross-sectional study in which an analysis was made of the culture and antibiogram reports of specimens taken from cases of conjunctivitis, infectious keratitis, and endophthalmitis between January 2013 and June 2016. Results: A total of 833 specimens were positive for bacteria. Considering both gram-positive and gram-negative microorganisms gentamicin, tobramycin, and ciprofloxacin showed high resistance rates (64.4%, 40.3%, and 29.1%, respectively). Moxifloxacin, vancomycin, imipenem, and gatifloxacin showed low percentages of resistance: 2.6%, 2.1%, 0.6%, and 0.4%, respectively. When comparing the results with previous studies in our institution, there was a decrease in sensitivity to the fourth-generation quinolones and imipenem, especially within the gram-negative ones. Conclusion: Fourth generation quinolones, imipenem and vancomycin continue to have a low in vitro resistance to bacteria that cause eye infections. However, there was a tendency to an increase in the resistance of gram-negative bacteria. Measures should be taken to try to control this phenomenon, and consider possible antimicrobial therapy alternatives to infections caused by these microorganisms

Anti-obesity effects of kaempferol by inhibiting adipogenesis and increasing lipolysis in 3T3-L1 cells.

Kaempferol is a natural flavonoid widely found in fruits, vegetables, and tea. Kaempferol possesses beneficial biological properties such as anti-inflammatory and antioxidant activities. Positive energy balance during obesity correlates with a pro-inflammatory chronic state. In this context, we hypothesized that kaempferol might promote anti-obesity effects by modulating adipogenesis and lipolytic pathways. Adipocyte viability at 24, 48, and 72 h was measured by an ATP-based assay. Pre-adipocytes (day 0) or mature adipocytes (day 12) were treated with 60 µM kaempferol until day 21 to evaluate its potential anti-adipogenic and lipolytic effect, respectively. Total lipid accumulation was assessed using Oil Red O staining assay. Gene expression was measured by RT-qPCR to evaluate the effect of kaempferol on adipogenesis and lipolysis gene expression. Our results showed a dose-dependent effect of kaempferol treatment on cell viability promoting cell death at higher than 60 µM concentration. Pre-adipocytes stimulation by 60 µM kaempferol resulted in 62% adipogenesis inhibition whereas in mature adipocytes, it reduced 39% intracellular lipid accumulation. Also, 60 µM kaempferol treatment decreased Cebpa mRNA expression when compared to control cells. In contrast, Pnpla2 and Lipe gene expression were upregulated in 3T3-L1 cells incubated with 60 µM kaempferol. In summary, our results showed that kaempferol modulates adipogenic differentiation in 3T3-L1 cells by promoting downregulation of Cebpa gene expression and decreasing lipid accumulation in mature adipocytes by its positive effects on Pnpla2 and Lipe mRNA levels. Kaempferol might display an anti-obesity effect.

Antibiotic resistance profile in eye infections in a reference centre in Floridablanca, Colombia. / Perfil de resistencia antibiótica en infecciones oculares en un centro de referencia en Floridablanca, Colombia.

BACKGROUND AND OBJECTIVE: In view of the increasing bacterial resistance to antibiotics, it is necessary to determine it locally in order to serve as a guide in clinical management. The purpose of this study was to characterise the pattern of antibiotic sensitivity in cases of eye infections in a third level ophthalmological institution in Floridablanca (Colombia). MATERIALS AND METHODS: An observational cross-sectional study in which an analysis was made of the culture and antibiogram reports of specimens taken from cases of conjunctivitis, infectious keratitis, and endophthalmitis between January 2013 and June 2016. RESULTS: A total of 833 specimens were positive for bacteria. Considering both gram-positive and gram-negative microorganisms gentamicin, tobramycin, and ciprofloxacin showed high resistance rates (64.4%, 40.3%, and 29.1%, respectively). Moxifloxacin, vancomycin, imipenem, and gatifloxacin showed low percentages of resistance: 2.6%, 2.1%, 0.6%, and 0.4%, respectively. When comparing the results with previous studies in our institution, there was a decrease in sensitivity to the fourth-generation quinolones and imipenem, especially within the gram-negative ones. CONCLUSION: Fourth generation quinolones, imipenem and vancomycin continue to have a low in vitro resistance to bacteria that cause eye infections. However, there was a tendency to an increase in the resistance of gram-negative bacteria. Measures should be taken to try to control this phenomenon, and consider possible antimicrobial therapy alternatives to infections caused by these microorganisms.

Queratitis micótica causada por Scedosporium apiospermum en paciente inmunocompetente / Mycotic keratitis caused by Scedosporium apiospermum in an immunocompetent patient

CASO CLÍNICO: Un hombre de 51 años inmunocompetente nos fue remitido por presentar una gran úlcera corneal con hipopion en el ojo derecho. Inicialmente se le indicó anfotericina B, fluconazol y moxifloxacina tópicos e itraconazol por vía oral. Ante el reporte de estructuras micóticas en la tinción se administró natamicina tópica. El cultivo fue reportado dos semanas después indicando: Scedosporium apiospermum (S. apiospermum). Se añadió entonces voriconazol tópico. La respuesta al tratamiento fue muy lenta y solo hasta cinco semanas después de estar recibiendo el manejo típico triconjugado (natamicina, voriconazol y fluconazol) y de una dosis intraestromal de voriconazol, desapareció el hipopion. El resultado final fue exitoso, lográndose la cicatrización de la úlcera. El paciente está en espera de trasplante de córnea. DISCUSIÓN: En pacientes en quienes se sospeche queratitis micótica es indispensable el estudio microbiológico. El manejo de elección ante S. apiospermum es el voriconazol, pero puede requerirse la combinación de diversos agentes antifúngicos

CLINICAL CASE: A 51 year-old immunocompetent male was referred due to presenting with a large corneal ulcer with hypopyon in the right eye. Topical amphotericin B, fluconazole and moxifloxacin, as well as oral itraconazole were initially indicated. Following the report of mycotic structures on staining, topical natamycin was started. The result of the culture was reported two weeks later as, Scedosporium apiospermum (S. apiospermum), and topical voriconazole was then added. The response to treatment was very slow, and took five weeks after receiving triple therapy (natamycin, voriconazole and fluconazole) and one dose of intrastromal voriconazole, for the hypopyon to disappear. The final outcome was successful, achieving healing of the ulcer. The patient is waiting for a corneal transplant. DISCUSSION: A microbiological study is essential in patients in whom fungal keratitis is suspected. The treatment of choice against S. apiospermum is with voriconazole, but the combination of various antifungal agents may be required

Intrathecal formation of anticardiolipin antibodies in a patient with SLE-related relapsing longitudinal myelitis: a possible pathogenic connection.

BACKGROUND: Nontraumatic acute transverse myelitis (ATM) can occur in response to infectious, inflammatory and vascular triggers; 1% of patients with systemic lupus erythematosus (SLE) develop ATM, but the mechanism remains unknown. OBJECTIVE: The objective of this case report is to describe a case of intrathecal formation of anticardiolipin antibodies (aCL) during SLE-related ATM. METHODS: A single patient analysis was conducted. RESULTS: A 26-year-old housewife was diagnosed with SLE at age 19. Circulating aCL antibodies were positive at diagnosis. At age 21, she developed an episode of severe sepsis. At 23 years of age she developed an episode of ATM that left her paraplegic with a D10 sensory level, from which she recovered partially. Three years later, she developed a clinical relapse of ATM. During that second episode, serum levels of aCL were within normal limits, while cerebrospinal fluid levels were increased, suggesting intrathecal production of aCL. CONCLUSION: Here, we present a case of a woman who developed relapsing SLE-related longitudinally extensive ATM in whom intrathecal formation of aCL was demonstrated, suggesting that local production and cross-recognition of nervous tissue by those autoantibodies may be myelopathic.

Mycotic keratitis caused by Scedosporium apiospermum in an immunocompetent patient. / Queratitis micótica causada por Scedosporium apiospermum en paciente inmunocompetente.

CLINICAL CASE: A 51 year-old immunocompetent male was referred due to presenting with a large corneal ulcer with hypopyon in the right eye. Topical amphotericin B, fluconazole and moxifloxacin, as well as oral itraconazole were initially indicated. Following the report of mycotic structures on staining, topical natamycin was started. The result of the culture was reported two weeks later as, Scedosporium apiospermum (S. apiospermum), and topical voriconazole was then added. The response to treatment was very slow, and took five weeks after receiving triple therapy (natamycin, voriconazole and fluconazole) and one dose of intrastromal voriconazole, for the hypopyon to disappear. The final outcome was successful, achieving healing of the ulcer. The patient is waiting for a corneal transplant. DISCUSSION: A microbiological study is essential in patients in whom fungal keratitis is suspected. The treatment of choice against S. apiospermum is with voriconazole, but the combination of various antifungal agents may be required.

Natural history of longitudinally extensive transverse myelitis in 35 Hispanic patients with systemic lupus erythematosus: good short-term functional outcome and paradoxical increase in long-term mortality.

Background and objective Acute transverse myelitis (TM) is an infrequent neurological complication of systemic lupus erythematosus (SLE). Short-term outcome varies widely between cohorts. Little is known about the epidemiology and long-term functional outcome of TM associated to SLE. Methods Patients with SLE and acute TM were identified during hospital admission, visits to the Emergency Room or the Neurology Outpatient Clinic. We evaluated ambispectively those patients with SLE presenting with clinical myelopathy and corroborated with spinal MRI. Cases were divided as partial (non-paralyzing) or complete (paralyzing). We determined long-term functional outcome as well as mortality in those patients with follow-up periods of at least five years. Results We identified 35 patients (partial, n = 15; complete, n = 20) in which complete clinical and imaging data were available (26 with follow-up ≥ 5 years). Patients with complete TM were significantly older than those with partial forms. Positive antiphospholipid antibodies were observed in 80% of patients, suggesting a possible mechanistical role. Surprisingly, functional recovery at one year was in general good; however, we observed a five-year mortality of 31% because of sepsis (in 10 cases) or pulmonary embolism (in one case). Conclusions Short-term outcome of SLE-related TM is generally good, and recurrence rate is low. However, we observed a long-term fatality rate of 31% for reasons unrelated to TM, suggesting that TM is a manifestation of severe immune dysregulation and a predictor of severity and mortality in patients with SLE.

Valor de la copeptina para la exclusión del infarto agudo de miocardio sin elevación del segmento ST en pacientes con dolor torácico y primera troponina negativa / Usefulness of copeptin in discarding non-ST elevation acute myocardial infarction in patients with acute chest pain and negative first troponin I

OBJETIVO: Evaluar la utilidad de la copeptina para descartar de forma rápida y segura el infarto agudo de miocardio sin elevación del segmento ST (IAMNST) en pacientes atendidos en un Servicio de Urgencias por dolor torácico agudo con electrocardiograma normal o no diagnóstico y primera determinación de troponina I (cTnI) negativa. DISEÑO: Estudio prospectivo y observacional. ÁMBITO: Servicio de Urgencias de un hospital universitario. PACIENTES: Un total de 97 pacientes atendidos en el Servicio de Urgencias por dolor torácico sugestivo de síndrome coronario agudo de menos de 12 h de evolución, con electrocardiograma no diagnóstico y primera cTnI negativa. INTERVENCIONES: Ninguna. VARIABLES DE INTERÉS: Datos demográficos y características basales, copeptina en admisión, cTnI en admisión y a las 6 h, diagnóstico final. RESULTADOS: El diagnóstico final fue de IAMNST en 14 pacientes (14,4%), no observándose diferencias significativas en las concentraciones de copeptina entre ambos grupos, aunque se observó una tendencia a valores superiores en aquellos con IAMNST (mediana: 24,6 pmol/L [amplitud intercuartil: 42,0] vs. 12,0 pmol/L [16,1]; p = 0,06). El AUC ROC para la medida al ingreso de copeptina fue de 0,657 (IC 95%: 0,504-0,810), con un valor predictivo negativo del 92% para un punto de corte de 14 pmol/L. CONCLUSIONES: La determinación de copeptina al ingreso en el Servicio de Urgencias en pacientes con dolor torácico ≤ 12 h sugestivo de síndrome coronario agudo, electrocardiograma no diagnóstico y primera TnI negativa no permite descartar de forma rápida y segura la presencia de IAMNST, siendo necesaria la realización de medidas seriadas de cTn

AIM: To evaluate the usefulness of copeptin as a rapid and reliable marker for discarding non- ST elevation acute myocardial infarction (NSTEMI) in patients attended in an Emergency Care Department due to acute chest pain with a normal or non-diagnostic electrocardiogram and a negative first troponin I result. Design: A prospective observational study was carried out. Setting: The Emergency Care Department of a university hospital. The study comprised a total of 97 patients attended in the Emergency Care Department due to chest pain suggestive of acute coronary syndrome with an evolution of under 12 h, a non-diagnostic electrocardiogram and a negative first troponin I result. Interventions: None. Variables of interest: Patient demographic data and baseline characteristics, copeptin upon admission, troponin I upon admission and after 6 h, and final diagnosis. Results: The final diagnosis was NSTEMI in 14 patients (14.4%) ---no significant differences in copeptin concentration being observed between the 2 groups, though a tendency towards higher values was recorded in the NSTEMI group (median: 24.6 pmol/l [interquartile range: 42.0] vs. 12.0 pmol/l [16.1]; P=.06). The AUC ROC for copeptin upon admission was 0.657 (95%CI: 0.504- 0.810), with a negative predictive value of 92% for a cutoff point of 14 pmol/l. Conclusions: Copeptin determination upon admission to the Emergency Care Department in patients with chest pain for ≤12 h, suggestive of acute coronary syndrome, with a non-diagnostic electrocardiogram and a negative first troponin I determination does not allow rapid and reliable exclusion of the presence of NSTEMI. Serial troponin I measurements are needed in this respect

[Usefulness of copeptin in discarding non-ST elevation acute myocardial infarction in patients with acute chest pain and negative first troponin I]. / Valor de la copeptina para la exclusión del infarto agudo de miocardio sin elevación del segmento ST en pacientes con dolor torácico y primera troponina negativa.

AIM: To evaluate the usefulness of copeptin as a rapid and reliable marker for discarding non-ST elevation acute myocardial infarction (NSTEMI) in patients attended in an Emergency Care Department due to acute chest pain with a normal or non-diagnostic electrocardiogram and a negative first troponin I result. DESIGN: A prospective observational study was carried out. SETTING: The Emergency Care Department of a university hospital. PATIENTS: The study comprised a total of 97 patients attended in the Emergency Care Department due to chest pain suggestive of acute coronary syndrome with an evolution of under 12h, a non-diagnostic electrocardiogram and a negative first troponin I result. INTERVENTIONS: None. VARIABLES OF INTEREST: Patient demographic data and baseline characteristics, copeptin upon admission, troponin I upon admission and after 6h, and final diagnosis. RESULTS: The final diagnosis was NSTEMI in 14 patients (14.4%) -no significant differences in copeptin concentration being observed between the 2 groups, though a tendency towards higher values was recorded in the NSTEMI group (median: 24.6pmol/l [interquartile range: 42.0] vs. 12.0pmol/l [16.1]; P=.06). The AUC ROC for copeptin upon admission was 0.657 (95%CI: 0.504-0.810), with a negative predictive value of 92% for a cutoff point of 14pmol/l. CONCLUSIONS: Copeptin determination upon admission to the Emergency Care Department in patients with chest pain for ≤12h, suggestive of acute coronary syndrome, with a non-diagnostic electrocardiogram and a negative first troponin I determination does not allow rapid and reliable exclusion of the presence of NSTEMI. Serial troponin I measurements are needed in this respect.

Neonatal presentation of incontinentia pigmenti with a family history extending over four generations--a case report.

We report a case of Incontinentia pigmenti (IP). A day 2 female presented to the special care nursery with seizures. EEG showed multifocal epileptiform discharges and cranial MRI revealed extensive cerebral infarction. A rash appeared shortly after birth. Eye examination revealed changes of IP. There is a strong family history of IP. Genetic testing excluded the most common mutation. Follow-up reveals significant development delay.

[Relationship of serum cortisol and metabolic syndrome components, dietary intakes and anxiety disorder in children at 8 to 12 years of age with obesity]. / Relación de cortisol sérico con los componentes del síndrome metabólico, ingesta alimentaria y trastorno de ansiedad en niños de 8 a 12 años con obesidad.

INTRODUCTION: Obesity is a disorder associated to an inappropriate food intake and psychological problems predisposing to complications such as metabolic syndrome (MS), which has been related to chronic stress due to hypercortisolism-mediated impairments of the hypothalamushypophysis-adrenal (HHA) axis activity. OBJECTIVE: To determine the relationship between serum cortisol and MS components, the food intake, and anxiety disorder in 8-12 years old obese children. METHODS: 78 children, 40 with obesity and 38 with appropriate weight. The following serum and clinical indicators were assessed: cortisol, glucose, HDL-cholesterol (c-HDL) and triglycerides; anthropometrical and clinical indicators: weight, height, body mass index (BMI), waist circumference (WC) and blood pressure (BP); food intake: deficient or excessive consumption and intake of energy and nutrients; psychological indicator: anxiety. RESULTS: There exists a significant relationship between cortisol level and the number of MS components in obese children (p < 0.05). When assessing the cortisol level against each one of these components, there were no significant differences. When analyzing the total sample, the cortisol level showed a negative relationship with c-HDL (r = -0.228, p = 0.045). We found a significant relationship between the cortisol level and excessive intake of foods of animal origin and sugars and with the subsets of fats and sugars (p < 0.05). There were no significant differences in energy or nutrients intake or anxiety in obese children. CONCLUSION: There exists a relationship between the cortisol level and the number of MS components as well as with excessive intake of foods of animal origin, sugars, and fats in obese children.

Enhancement of recombinant hemoglobin production in Escherichia coli BL21(DE3) containing the Plesiomonas shigelloides heme transport system.

To produce recombinant hemoglobin in Escherichia coli, sufficient intracellular heme must be present, or the protein folds improperly and is degraded. In this study, coexpression of human hemoglobin genes and Plesiomonas shigelloides heme transport genes enhanced recombinant hemoglobin production in E. coli BL21(DE3) grown in medium containing heme.

Prenatal morphine exposure attenuates the maintenance of late LTP in lateral perforant path projections to the dentate gyrus and the CA3 region in vivo.

Previously we reported that prenatal exposure to morphine twice daily during gestation decreases proenkephalin levels in adult progeny within the brain, including the dentate gyrus, and alters mu and delta opioid receptors in the hippocampal CA3 region. The lateral aspect of the perforant path contains and releases enkephalin-derived opioid peptides, and induction of long-term potentiation (LTP) in lateral perforant path projections to both the dentate gyrus and the hippocampal CA3 region is blocked by antagonists of opioid receptors. Thus LTP induction at these synapses involves opioid receptor activation mediated by the release of proenkephalin-derived opioid peptides with lateral perforant path activation. Here we show in adult behaving animals, neither LTP induction nor the early phase of LTP (E-LTP) maintenance is altered by prenatal morphine exposure in the lateral perforant path projections to the dentate gyrus and the CA3 region. However, maintenance and longevity of late LTP (L-LTP), as reflected in the magnitude of LTP over days, was attenuated in animals prenatally exposed to morphine. In contrast, in medial perforant path projections to the dentate gyrus and CA3 region, both LTP induction and the maintenance of E- and L-LTP were unaffected by prenatal morphine treatment. Thus a brief prenatal exposure to the opiate morphine produces sustained, and possibly permanent, alterations in L-LTP in the opioidergic lateral perforant path projection. This suggests that prenatal morphine exposure disrupts LTP via disruption of opioid mechanisms involved in LTP maintenance or via disruption of opioid receptor activation during LTP induction, which can subsequently alter LTP maintenance.

A comparison of the neurotropism of Theiler's virus and poliovirus in CBA mice.

Theiler's murine encephalomyelitis virus (TMEV) and poliovirus infect the central nervous system (CNS) and cause neurological damage. The exact route by which TMEV and polioviruses enter the CNS remains, for the most part, unknown, although the neural and/or the hematogenous pathway have both been postulated. To explore these hypotheses, this research focuses on both the site of entry and the pathway used to invade the CNS. Following different inoculation sites of the GDVII strain of Theiler's virus or Lansing Type 2 poliovirus in CBA mice, the incidence of paralysis and/or encephalitis was evaluated on the basis of clinical signs and histopathology. The forms of paralysis displayed corresponded to the site of viral inoculation. Following intramuscular (i.m.), intraperitoneal (i.p.), and footpad routes of injection, bilateral and or contralateral paralyses were observed for both TMEV and poliovirus. In mice injected intratongue and in the hypoglossal nerve, tongue paralysis or paralysis of the forelimb, which progressed to bilateral forelimb paralysis, was observed, additionally the penis of most infected males was protruded. Intracranial (i.c.) injections with type II poliovirus strain resulted in forelimb paralysis. Intravenous (i.v.), injections with TMEV also resulted in forelimb paralysis. Thus Lansing Type II poliovirus and TMEV infections of CBA mice, result in similar incidence of paralysis and histopathological findings.

Families' perception of the value of timed daily "family rounds" in a trauma ICU.

Daily communications between the ICU trauma patients' families and the trauma team are often limited due to the unpredictable nature of subsequent patient admissions and operative procedures. In order to improve the lines of family-physician communication and educate residents regarding family communication, our level I trauma center instituted daily "Family Rounds" (FR). FR occur at the same time every day, in the patient's ICU room. The purpose of this study was to determine whether families valued the scheduled daily FR, to establish whether FR improved the family-physician relationship, and to delineate strengths and weaknesses of the present structure of our FR. We mailed surveys to family members of trauma patients hospitalized in the trauma ICU for > or = 3 days. A total of 55 (22%) families responded. Combining "excellent" and "good" responses, 86.5 per cent of families looked forward to having a specific time of day to meet with the trauma team, and 90 per cent liked having rounds in the ICU room with the patient. However, 36 per cent did not like having only scheduled time for FR. The majority, 75 per cent, believed that all concerns were addressed during FR, and 84.9 per cent rated their overall experience as either excellent or good. Scheduled FR appear to improve communication between trauma surgeons and patients' families, enhance the family-physician relationship, and strengthen our surgical residency teaching program.

Osteoblast responses to as-deposited and heat treated sputtered CaP surfaces.

The clinical success of dental implants is governed by implant surfaces and bone cell responses that promote rapid osseointegration. The objective of this study was to evaluate the in vitro osteoblast cell response to heat treated and non-heat treated CaP coatings. In this study, the heat treated surfaces exhibited a poorly crystallized HA-type structure whereas the non-heat treated surface exhibited an amorphous structure. The heat treated CaP surfaces were observed to have a mean contact angle measurement of 57.95+/-0.95 degrees, whereas the non-heat treated CaP surfaces were observed to have a mean contact angle measurement of 44.6+/-0.3 degrees. From the in vitro cell culture study, the ATTC CRL 1486 human embryonic palatal mesenchyme (HEPM) cells displayed a similar protein production and hexosaminidase activity on the heat treated and non-heat treated CaP surfaces throughout the nine day experiment. However, the HEPM cells cultured on non-heat treated CaP surfaces were observed to have higher specific ALP activity after nine days' incubation compared to cells cultured on heat treated CaP surfaces. The higher specific ALP activity by cells on non-heat treated surfaces were suggested to be attributed to the lower degree of crystallinity and the lower contact angles observed in this study.

Effects of renal denervation on the sodium excretory actions of leptin in hypertensive rats.

BACKGROUND: Previous studies from this laboratory have reported a marked attenuation of the renal responses to pharmacologic doses of synthetic murine leptin infused in the spontaneously hypertensive rat (SHR) model compared with normotensive Sprague-Dawley and lean Zucker rat models. METHODS: In the present study, the hemodynamic and renal excretory effects of an intravenous bolus administration of pharmacologic doses of synthetic murine leptin were examined in groups of anesthetized SHR with unilateral nephrectomy and renal denervation or sham-denervation of the remaining kidney. RESULTS: In the SHR with acute renal denervation (N = 8), an intravenous bolus of 1600 microg/kg of leptin produced a significant twofold to fourfold elevation in sodium excretion but did not increase natriuresis in the sham-denervated group (N = 6). Chronic renal denervation of one-week duration (N = 8) was associated with qualitatively and quantitatively similar increases of sodium excretion in response to leptin administration. Mean arterial pressure remained unchanged in all groups after the administration of leptin. CONCLUSIONS: Collectively, these results are interpreted to suggest that the blunted natriuretic and diuretic responses to leptin observed in the SHR with intact renal nerves may be partially explained by the antinatriuretic effect of an enhanced baseline efferent renal sympathetic activity and/or leptin's stimulation of the sympathetic nervous system.

Modulation of renin secretion by atrial natriuretic factor prohormone fragment 31-67.

BACKGROUND: Earlier studies have indicated that the atrial natriuretic factor prohormone fragment 31-67 (Pro ANF31-67) has important effects for the promotion of sodium excretion and vasodilation in several animal species. However, the mechanisms for the natriuretic actions of Pro ANF31-67 are not completely defined. In the present study, the effects of synthetic Pro ANF31-67 on renin secretion were examined in sodium-depleted, anesthetized dogs with a single intact kidney (n = 5). METHODS: After 3 20-minute control renal clearance periods, synthetic dog Pro ANF31-67 was given intrarenally at a sustained dose of 0.03 microg/kg/min for 3 20-minute experimental intervals, and after discontinuation of the peptide infusion, 3 final 20-minute recovery periods were determined. RESULTS: Sustained intrarenal infusions of the Pro ANF31-67 produced striking decrements (p<0.05) in renin secretion, from a control value of 1418 +/- 243 to 401 +/- 223 ng of angiotensin I/min. This 66% fall in renin secretion was associated with significant (P < 0.05) increases in creatinine clearance (40%), renal blood flow (8%), urine flow (50%), and sodium excretion (17%). CONCLUSIONS: It is suggested that this inhibition of renin secretion was mediated, at least in part, in response to a ProANF31-67-induced increment in the sodium load delivered to the macula densa. An interaction of the peptide with the renal vascular receptor for suppression of renin release is also possible. ProANF31-67 may represent an important hormonal mechanism involved in the regulation of body-fluid balance.

Hemodynamic and renal effects of ProANF31-67 in hypertensive rats.

It has been demonstrated previously that the atrial natriuretic factor prohormone fragment 31-67 (ProANF31-67) circulates in animals and possesses natriuretic and vasodilating actions. Although the plasma levels of the peptide are reportedly elevated in patients with high blood pressure, its role and actions in hypertension are unknown. In the present study, synthetic human ProANF31-67 was infused intravenously at doses of 0, 10, 30, and 100 ng/kg/min into respective groups of anesthetized normotensive and spontaneously hypertensive rats. Mean arterial pressure (MAP), urine flow rate (UV), and sodium excretion (UNaV) were measured during two consecutive 30-min periods. In both strains of rats, reductions in MAP with ProANF31-67 were similar in magnitude and dose-related. Sodium excretion responses to the peptide infusions also were remarkably similar in both normotensive and hypertensive rats, and the responses demonstrated 3- to 5-fold (P < 0.05) increments compared to control at the doses of 10 and 30 ng/kg/min. However, in the two strains of rats, attenuation of natriuresis occurred with the highest infusion dose of 100 ng/kg/min and was probably related to the large decreases in MAP of 17-23 mmHg at this dose of the peptide. The present results indicate the ProANF31-67 has important hemodynamic and renal effects in hypertension and may represent one compensatory mechanism involved in this disease.