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Background and Objectives: Lower extremity arterial disease is one of the most prevalent manifestations of atherosclerosis. The results from numerous studies regarding the best revascularization method of an occluded superficial femoral artery have been conflicting. The aim of this study was to compare the patency of transvenous endovascular with open femoropopliteal bypass, both with vein and prosthetic grafts. To our knowledge, a direct patency comparison between transvenous endovascular and open femoropopliteal bypass has not been published. This could help elucidate which method is preferable and in which cases. Materials and Methods: Patients with complex TASC-C and D SFA lesions were offered endovascular transvenous or open bypass. A total of 384 consecutive patients with PAD requiring surgical treatment were evaluated for inclusion in this study. Three-year follow-up data were collected for 52 endovascular procedures, 80 prosthetic grafts, and 44 venous bypass surgeries. Bypass patency was investigated by Duplex US every 6 months. Kaplan-Meier plots were used to analyze primary, primary-assisted, and secondary patency for endovascular transvenous, autovenous, and prosthetic bypasses. Results: Primary, primary-assisted, and secondary patency in venous group at 3 years was 70.5%, 77.3%, and 77.3%, respectively. In the endovascular transvenous group, primary, primary-assisted, and secondary patency at 3 years was 46.2%, 69.2%, and 76.9%, respectively. The lowest patency rates at 3 years were noted in the prosthetic graft group with 22.5% primary, 26.6% primary-assisted, and 28.2% secondary patency. Conclusions: The saphenous vein is the best graft to perform in above-the-knee femoropopliteal bypass. Transvenous endovascular bypass is a viable option with comparable primary-assisted and secondary patency. Primary patency is substantially lower for endovascular transvenous compared to venous bypass. Patients treated with endovascular transvenous bypass will require a significant number of secondary procedures to provide optimal patency. Prosthetic grafts should only be used if no other option for bypass is available.

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Since the 19th century, it has been known that the carnivorous Venus flytrap is electrically excitable. Nevertheless, the mechanism and the molecular entities of the flytrap action potential (AP) remain unknown. When entering the electrically excitable stage, the trap expressed a characteristic inventory of ion transporters, among which the increase in glutamate receptor GLR3.6 RNA was most pronounced. Trigger hair stimulation or glutamate application evoked an AP and a cytoplasmic Ca2+ transient that both propagated at the same speed from the site of induction along the entire trap lobe surface. A priming Ca2+ moiety entering the cytoplasm in the context of the AP was further potentiated by an organelle-localized calcium-induced calcium release (CICR)-like system prolonging the Ca2+ signal. While the Ca2+ transient persisted, SKOR K+ channels and AHA H+-ATPases repolarized the AP already. By counting the number of APs and long-lasting Ca2+ transients, the trap directs the different steps in the carnivorous plant's hunting cycle. VIDEO ABSTRACT.

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The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula's trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair's sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula's hapto-electric signaling.

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Childhood trauma (CT) is a risk factor for schizophrenia spectrum disorders (SSDs), and cognitive impairment is a core feature and a vulnerability marker of SSDs. Studies of the relationship between CT and cognitive impairment in SSDs are inconclusive. In addition, few studies have examined differential effects of CT subtypes, e.g. physical, sexual or emotional abuse/neglect, on cognitive functioning. The present study therefore aimed to examine the effects of CT and CT subtypes on cognitive impairment in SSD. Participants (n = 78) with SSDs completed a comprehensive neuropsychological test battery and the Childhood Trauma Questionnaire Short-Form (CTQ-SF). We compared global cognitive performance as well as scores in seven subdomains (verbal abilities, visuospatial abilities, learning, memory, attention/working memory, executive abilities and processing speed) between participants reporting no CT and those reporting CT experiences using independent samples t-tests as well as linear regression analyses to control for possible confounders. CT subtype physical neglect was associated with attention and working memory after controlling for positive and negative psychosis symptoms, years of education, antipsychotics, gender and age, and adjustment of multiple testing. Our results indicate that the observed heterogeneity in cognitive impairment in SSDs, especially attention/working memory abilities, may in part be associated with childhood physical neglect.

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Chiral rodlike colloids exposed to strong depletion attraction may self-assemble into chiral membranes whose twisted director field differs from that of a 3D bulk chiral nematic. We formulate a simple microscopic variational theory to determine the elastic moduli of rods assembled into a bidimensional smectic membrane. The approach is based on a simple Onsager-Straley theory for a non-uniform director field that we apply to describe rod twist within the membrane. A microscopic approach enables a detailed estimate of the individual Frank elastic moduli (splay, twist and bend) as well as the twist penetration depth of the smectic membrane in relation to the rod density and shape. We find that the elastic moduli are distinctly different from those of a bulk nematic fluid, with the splay elasticity being much stronger and the curvature elasticity much weaker than for rods assembled in a three-dimensional nematic fluid. We argue that the use of the simplistic one-constant approximation in which all moduli are assumed to be of equal magnitude is not appropriate for modelling the structure-property relation of smectic membranes.

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We theoretically investigate the pitch of lyotropic cholesteric phases composed of slender rods with steric chirality transmitted via a weak helical deformation of the backbone. In this limit, the model is amenable to analytical treatment within Onsager theory and a closed expression for the pitch versus concentration and helical shape can be derived. Within the same framework, we also briefly review the possibility of alternative types of chiral order, such as twist-bend or screw-like nematic phases, finding that cholesteric order dominates for weakly helical distortions. While long-ranged or "soft" chiral forces usually lead to a pitch decreasing linearly with concentration, steric chirality leads to a much steeper decrease of quadratic nature. This reveals a subtle link between the range of chiral intermolecular interaction and the pitch sensitivity with concentration. A much richer dependence on the thermodynamic state is revealed for polar helices where parallel and anti-parallel pair alignments along the local director are no longer equivalent. It is found that weak temperature variations may lead to dramatic changes in the pitch, despite the lyotropic nature of the assembly.

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We investigate the emergence of chiral meso-structures in one-dimensional fluids consisting of stacked discotic particles and demonstrate that helical undulations are generated spontaneously from internal elastic stresses. The stability of these helical conformations arises from an interplay between long-ranged soft repulsions and nanopore confinement which is naturally present in columnar liquid crystals. Using a simple mean-field theory based on microscopic considerations we identify generic scaling expressions for the typical buckling radius and helical pitch as a function of the density and interaction potential of the constituent particles.

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Monte Carlo computer simulations are carried out for a model system of like-charged colloidal platelets in the isothermal-isobaric ensemble (NpT). The aim is to elucidate the role of electrostatic interactions on the structure of synthetic clay systems at high particle densities. Short-range repulsions between particles are described by a suitable hard-core model representing a discotic particle. This potential is supplemented with an electrostatic potential based on a Yukawa model for the screened Coulombic potential between infinitely thin disklike macro-ions. The particle aspect-ratio and electrostatic parameters were chosen to mimic an aqueous dispersion of thin, like-charged, rigid colloidal platelets at finite salt concentration. An examination of the fluid phase diagram reveals a marked shift in the isotropic-nematic transition compared to the hard cut-sphere reference system. Several statistical functions, such as the pair correlation function for the center-of-mass coordinates and structure factor, are obtained to characterize the structural organization of the platelets phases. At low salinity and high osmotic pressure we observe anomalous hexagonal columnar structures characterized by interpenetrating columns with a typical intercolumnar distance corresponding to about half of that of a regular columnar phase. Increasing the ionic strength leads to the formation of glassy, disordered structures consisting of compact clusters of platelets stacked into finite-sized columns. These so-called "nematic columnar" structures have been recently observed in systems of charge-stabilized gibbsite platelets. Our findings are corroborated by an analysis of the static structure factor from a simple density functional theory.

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OBJECTIVE: To determine the prevalence and clinical significance of human parvovirus B19 (B19) infection in patients with rheumatoid arthritis (RA). METHODS: One hundred patients with RA and 94 apparently healthy blood donor controls were enrolled for study. Plasma samples of patients and controls were examined for the presence of anti-B19-specific antibodies by ELISA. B19 DNA was detected in plasma and peripheral blood leukocyte (PBL) samples of all patients and controls as well as in synovial fluid cells of 38 RA patients by nested polymerase chain reaction. Disease activity and clinical manifestations were determined in RA patients with and without markers of B19 infection. RESULTS: IgM anti-B19-specific antibodies were detected in 24.0% of RA patients; B19 DNA was found in plasma and/or PBL, synovial fluid cells in 34.0% (34 patients); in 14.0% of the cases (14 patients) both markers were found. In blood donor controls, anti-B19 IgM antibodies were observed in 16.0% (15 donors) and B19 DNA in 6.4% (6 donors); all donors with detectable B19 genomic DNA were IgM-positive. The disease activity in patients with and without B19 infection was similar, while the frequency of clinical complications was significantly higher in the patients with anti-B19 IgM antibodies. Moreover, liver failure and sicca syndrome were observed in the viremic patients only. CONCLUSION: Our study confirms observations regarding a high prevalence of B19 DNA in patients with RA, and a possible role of this viral infection in the pathogenesis of RA.

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We made a prospective, population-based study of external version attempt in the department of obstetrics at Hospital, Clínica y Maternidad Conchita A.C. at Monterrey, N.L. 45 patients were enrolled with diagnosis of breech presentation. We tested the hypothesis to determined the average of success and how this procedure can reduce the primary C section rate. Of the 45 patients, 48.9% were primiparous, we had success in the external version in 27 patients (60%), 81.4% had vaginal delivery and 18.6% C section. During the study the incidence of primary C section in breech presentation shown low rates from 15.3% to 9.3%. We did'nt have complications in the procedure. With these results, we concluded that the attempt of external version is more safety and had less risks for the mother and fetus that breech delivery, and we can reduced the primary C section rate for this indication.

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Breast cancer is the second malignant tumor that affects women in our population. The fine needle biopsy is a sensitive and specific technique. The purpose for this study was to show our experience at our institution. The fine needle biopsy was performed in 22 patients with diagnosis of breast tumor; all were surgically treated. In all the cases the initial cytology showed a high correlation with final histology findings. There were no complications. It was concluded that with an adequate fine needle biopsy technique, results correlate well with histopathologic study, with high sensitivity and specificity. This technique is easy to perform, with a low cost, and it may be considered as an useful tool in the study of patients with breast tumors.

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The macrosomia is an obstetric eventuality associated to high maternal-fetal morbidity-mortality. This assay was planned in order to know the incidence of macrosomia in our institution, the relation between vaginal and abdominal deliveries and the fetal-maternal morbidity we reviewed 3590 records and we found 5.6% incidence of macrosomia in the global obstetric population. There was 58% of vaginal deliveries, 68% of the newborn were male. The main complications were in the C. sections, 2 laceration of the hysterectomy, and 2 peroperative atonias. In the vaginal deliveries, the lacerations of III and IV grade were 9 of each grade. The main fetal complications were 5 slight to severe asphyxia and 4 shoulder dystocias. This assay concludes that the macrosomia in our service is similar to the already published ones, a 42% were C. section and the maternal-fetal morbidity was low.

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This report refers to the case of a 39-year-old woman, fourth gestation, who during her first pregnancy developed neurologic deficit of the left hand, which slowly progressed getting to affect during seven years, all the left upper extremity and the right hand. During this time, she had two abortions, and between the third and fourth pregnancies, because of the clinical suspicion, laboratory tests were done, finding by electromyography, lesion of anterior process of spinal chord at cervical level. During this fourth pregnancy, neurologic deficit increased and it was decided to interrupt pregnancy by cesarean section under epidural block at 38 weeks of gestation. According to our knowledge this syringomyelia case and pregnancy, is the first one reported in our country.

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A retrospective study to determine the risks of normal delivery after cesarean section, was done. The inclusion criteria were found in 116 patients in six years covering the study. All the patients were permitted normal delivery and none received ocitocin. Sixty six patients accomplished delivery, which corresponds to 57%. In the rest of patients cesarean section was performed. The probability of ending in delivery was associated to women with three or more gestas. But cephalo-pelvic disproportion and fetal suffering, were associated to greater probability of ending in cesarean section. There was no dehiscence of uterine scar. It is concluded that with well established requisites it is possible to resolve by delivery with a great degree of confidence, at least 50% of cases with previous section.

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When delivery induction with an unfavorable cervix, is required, the traditional conduct has been to use oxitocin and more recently prostaglandins as gel. The purpose of this report is to communicate the experience of a prospective work with a group of 48 patients with amenorrhea from 16 to 42.5 weeks of gestation with an unfavorable cervix. The idea was to modify cervical features in order to facilitate delivery induction in patients with the following diagnosis: 1, Prolonged pregnancy in 32 patients. 2. Severe pre-eclampsia in seven. 3. High blood pressure in five. 4. Intrauterine growth retardation in four. All the patients were evaluated with a Bishop index of three or less. The procedure consisted of introduction of a No. 14 or 16 Foley catheter through the cervical canal, filling the balloon with 30 ml, and simultaneous application of intravenous oxitocin controlled with an infusion pump. Cervical maturation was seen in all the patients, time was from 2 to 24 hours. In all the cases Bishop's index was greater than five after the procedure. Delivery via was vaginal in 26 patients, and cesarean section in 22. There were no infectious complications, nor other type in women nor in newborns. It was concluded that despite criticism, this procedure has shown to be useful, dependable, to mature the cervix, its is available for all gyneco-obstetricians and easy to carry out.

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Cuando se requiere la inducción del parto con una cervix desfavorable, lo tradicional ha sido utilizar la oxitocina endovenosa y más recientemente las prostaglandinas en su forma de gel. El propósito de este informe es comunicar la experiencia de un trabajo prospectivo en un grupo de 48 pacientes con amenorrea entre 36 y 42.5 semanas de gestación con un cérvix desfavorable. La finalidad fue modificar las características cervicales para facilitar la inducción del parto en pacientes que tenían los siguientes diagnósticos: 1. Embarazo prolongado en 32 pacientes. 2. Pre-eclampsia severa en siete. 3. Hipertensión arterial en cinco, y 4. Retardo en el crecimiento intrauterino en cuatro. A todas las pacientes se les evaluó con un índice de Bishop de tres o menos. El procedimiento consistió en la introducción de una sonda de Foley No. 14 o 16 a través del canal cervical, llenado el balón con 30 ml. y aplicación simultánea de oxitocina endovenosa controlado con una bomba de infusión. La maduración del cervix se observó en todas las pacientes, oscilando el tiempo necesario entre 2 y 24 horas. En todos los casos el índice de Bishop fue mayor de cinco después del procedimiento. La vía de nacimiento fue vaginal en 26 pacientes y en 22 por operación cesárea. No se observaron complicaciones infecciosas ni de otra naturaleza en madres ni en los recién nacidos. Se concluye que a pesar de las críticas, este procedimiento ha mostrado ser útil, confiable, para madurar el cervix, al alcance de cualquier Gineco-Obstetra y fácil de realizar

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The incidence of premature rupture of membranes in pregnancies of 36 weeks or less, in relation to the total births (3,796) is 1.3%; in relation to pregnancies less than 36 weeks (49 cases) 21.5%, and in pregnancies of less than 34 weeks (17 cases) of 0.47%. Infectious mortality was 2.2%. There was no maternal mortality. Cesarean section incidence was 43%. Neonatal infectious morbidity was present in 16.3%. Neonatal mortality on 4/30 cases was 13.0%; global mortality at two years was 5/30 cases, 17.0%.

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The objective of this investigation was to determine the effectiveness of ampicillin administration as a prophylactic regime in patients undergoing cesarean section. A double blind randomized study compared a long course of ampicillin (7 days) to a short course of ampicillin (three doses) to placebo. Thirty one patients were included in the placebo group and sixty patients in the drug groups. Only one patient in the placebo group and one in the drug group developed infectious morbidity. There was no significant difference (p less than 0.001) between the placebo and ampicillin groups.

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The goal of the present study was to follow the clinical behaviour of 6 non diabetic patients (5 females and 1 male, aged 23-68) suffering from necrobiosis lipoidica. Thickening of the basalmembrane of capillaries could be confirmed by electron microscopy, although the histological structure of skin alterations are not different from those observed in diabetes mellitus. Three patients (2 females and one male) showed impaired glucose tolerance, 2 other patients had increased levels of total cholesterol, whereas one patient suffered from both metabolic disturbances. After treatment with ASA (acetylsalicylic acid, 1.0 g/day) and dipyridamole (200 mg/day) for six weeks, the decrease of platelet in vitro aggregation in platelet rich plasma could be observed by stimulation with arachidonic acid, epinephrine, ADP and collagen, respectively. Healing of the exulceration of skin lesion could be detected by the use of the combined treatment of ASA and dipyridamole in 4 cases.

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The authors have verified that retina dysfunction in patients suffering from chronic pancreatitis could be demonstrated by the help of electroretinography and eliminated or significantly corrected by administration of pancreas enzyme preparations. The retinograph may be applied successfully in the diagnosis of chronic pancreatitis and also in evaluation of the efficacy of the substitution treatment. The insufficiency of zinc absorption may play a definite role in the development of these functional disturbances. It has also been established that lower zinc values parallel with the decrease of the stool fat contents in patients suffering from chronic pancreatitis and can be significantly improved by enzyme preparations.

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