Doble anomalía de la segunda hendidura branquial

Second branchial cleft anomalies are the most common of this type of neck masses. They can be classified in four types (Bailey/Proctor classification) according to their location. Type II is the most common, and related to vital neck structures such as the carotid artery and jugular vein. Cysts are the most frequent among them. Management consists of surgical excision of the cyst and tract by cervicotomy to avoid recurrence. We present an extremely rare case of a 32-year-old male who presented a sudden appearance of a right lateral neck mass that was identified by an image study as a double branchial cleft cyst. A review of simultaneous branchial cleft cyst in the literature is also made.     

Hindlimb claudication reflects impaired nitric oxide-dependent revascularization after ischemia

Although vascular remodeling is important in preventing tissue damage and restoring muscle function, there is no evidence of a relationship between vascular remodeling and muscle function after peripheral vascular occlusion. Nitric oxide (NO) has been implicated in the process of vascular remodeling in hindlimb ischemia. Thus, development of alterations in hindlimb gait after ischemia may be associated with impaired nitric oxide-dependent, vascular blood flow recovery. We evaluated hindlimb gait as an index of ischemia-induced revascularization and tested the effects of NO synthase inhibition on both hindlimb blood flow and hindlimb gait locomotion. After 14 days of ischemia, the ischemic hindlimb showed no significant differences in gait locomotion compared to the sham-operated hindlimb. However, hindlimb ischemia drastically reduced hindlimb blood flow from 46+/-3 mL/min/100 g to 12+/-2 mL/min/100 g which reverted to 33+/-5 mL/min/100 g after 14 days of ischemia. eNOS mRNA expression levels at 3, 7, 14, and 28 days after initiation of ischemia, were increased by 50+/-5%, 100+/-10%, 140+/-8% and 270+/-12% respectively and eNOS protein expression levels at 7, 14, and 28 days, were increased by 28+/-3%, 62+/-6% and 80+/-16% respectively. However, eNOS inhibition caused by l-NAME treatment prevented blood flow recovery and correction of abnormal gait locomotion in rats. Thus, the duration of the stride-swing phase increased and the stride length decreased. The knee joint angle decreased during flexion and extension with eNOS inhibition. In conclusion, ischemia-induced revascularization is associated with recovery of both hindlimb blood flow and normal gait locomotion. Moreover, prevention of NO synthesis, a key messenger in ischemia-induced revascularization, is associated with impairment in hindlimb locomotion. Thus, gait locomotion represents a functional model that could be used to evaluate the degree of ischemia-induced revascularization.     

Central nervous system depressant activity of an ethyl acetate extract from Ipomoea stans roots

Ipomoea stans Cav., popularly known as "tumbavaqueros", is a plant widely used in Mexico for the treatment of epileptic seizures and nervous disorders. This work researched the action of the ethyl acetate extract from the root of I. stans (IS-EAE) on the central nervous system (CNS). The administration of IS-EAE (2.5 and 5.0 mg/kg, i.p.) produced an anxiolytic effect in mice. This extract (20.0 and 40.0 mg/kg, i.p.) significantly reduced spontaneous motor activity. 2.5, 5.0, 10.0, and 20.0 mg/kg of IS-EAE protected mice against pentylenetetrazole-induced convulsions and increased the hypnotic effect induced by pentobarbital. The administration of IS-EAE was able to increase the release of GABA in brain cortex of mice. These results suggest that IS-EAE possess anxiolytic and anticonvulsant effects, and could have potential sedative effect, probably through a GABAergic system. The extract did not show antidepressant effects on mice exposed to forced swimming test.     

CYP2C9 structure-metabolism relationships: substrates, inhibitors, and metabolites

The cytochrome P450 (CYP) family is composed of monooxygenases, which mediate the metabolism of xenobiotics and endogenous compounds. The characterization of the interactions between these enzymes and candidate drugs is an important part of the drug discovery process. CYP2C9, one isoform of the CYPs, mediates the oxidation of several important drugs. The aim of this work is to investigate the possibility to study inhibition and substrate interactions with CYP2C9, using docking and the site of metabolism predictions. The model compounds used for the study were the COX-2 inhibitor celecoxib and a series of 13 analogues known to be metabolized by CYP2C9. The results obtained using the two methods gave valuable information about important interactions of inhibitors and substrates with CYP2C9. The two methods could be used to predict the site of metabolism and to determine the productive docking pose for each compound. These predictions were verified by metabolite identification using LC/MS/MS after incubation with recombinant CYP2C9.     

The annual impact of seasonal influenza in the US: measuring disease burden and costs

BACKGROUND: Despite preventive efforts, influenza epidemics are responsible for substantial morbidity and mortality every year in the United States (US). Vaccination strategies to reduce disease burden have been implemented. However, no previous studies have systematically estimated the annual economic burden of influenza epidemics, an estimate necessary to guide policy makers effectively. OBJECTIVE: We estimate age- and risk-specific disease burden, and medical and indirect costs attributable to annual influenza epidemics in the United States. METHODS: Using a probabilistic model and publicly available epidemiological data we estimated the number of influenza-attributable cases leading to outpatient visits, hospitalization, and mortality, as well as time lost from work absenteeism or premature death. With data from health insurance claims and projections of either earnings or statistical life values, we then estimated healthcare resource utilization associated with influenza cases as were their medical and productivity (indirect) costs in $2003. RESULTS: Based on 2003 US population, we estimated that annual influenza epidemics resulted in an average of 610,660 life-years lost (undiscounted), 3.1 million hospitalized days, and 31.4 million outpatient visits. Direct medical costs averaged $10.4 billion (95% confidence interval [C.I.], $4.1, $22.2) annually. Projected lost earnings due to illness and loss of life amounted to $16.3 billion (C.I., $8.7, $31.0) annually. The total economic burden of annual influenza epidemics using projected statistical life values amounted to $87.1 billion (C.I., $47.2, $149.5). CONCLUSIONS: These results highlight the enormous annual burden of influenza in the US. While hospitalization costs are important contributors, lost productivity from missed work days and lost lives comprise the bulk of the economic burden of influenza.