Head-space gas chromatography coupled to mass spectrometry for the assessment of the contamination of mayonnaise by yeasts.

Head-space (HS) gas chromatography (GC) coupled to mass spectrometry (MS) is proposed for the assessment of the contamination of mayonnaise as an alternative to plate counting, which is the technique commonly used for evaluating microbial contamination. More specifically, this method was applied in the detection of Candida metapsilosis and Zygosaccharomyces bailii, both of great importance in term of food spoilage since they are resistant to many of the common methods of food preservation. Different chemometric models were investigated using the data obtained by GC-MS (m/z profile, area of the chromatographic peaks and entire chromatographic profile), in order to obtain the highest classification success. The best results were obtained using the chromatographic profile (success rate of 92%). Contaminated samples could also be classified according to the concentration of yeast, obtaining a success rate of 87.5%. Finally, a chemometric model was constructed in an attempt to differentiate between strains.

Reasons why erupted third molars are extracted in a public university in Mexico.

PURPOSE: The aim of this study was to determine the reasons for which erupted third molars (3M) are extracted in a sample of Mexican patients. SUBJECTS AND METHODS: A retrospective cross-sectional study was performed on a sample of 83 patients attending exodontia (minor oral surgery) clinics of a public university in Mexico (Autonomous University of Hidalgo State). The outcome variable was the reason for extractions using Kay and Blinkhorn's classification. The independent variables were age, gender, arch and tooth number according to the World Health Organization (WHO). For statistical analysis, we used the Chi-squared test in Stata 9.0. RESULTS: Eighty-three patients underwent 150 3M extractions. Mean age was 38.67 ± 13.96 years, and 71.1% were female. The four reasons for 3M extraction were prosthetic (44.0%), followed by orthodontic (24.7%), dental caries (20.0%) and periodontal disease (11.3%). Differences were observed in the reasons for 3M extractions across age groups (p < 0.05). No significant differences existed between men and women (p > 0.05), or the WHO tooth number (p > 0.05). CONCLUSION: Women and patients 18 to 34 years of age had erupted 3M extracted more frequently, primarily for prosthetic reasons. The age profile indicated a trend in demand for services that differ from those of overall tooth extractions, but not for the trend across gender.

Morphometric analysis of potential osteochondral autografts for resurfacing unicondylar defects of the proximal phalanx in PIP joint injuries.

PURPOSE: This study was designed to morphometrically assess the base of the little and ring finger metacarpals as potential osteochondral donors to resurface distal condylar defects of the proximal phalanx. METHODS: The proximal phalanges were dissected from all 4 fingers in 10 cadaveric hands and the following measurements were obtained from the distal condylar surface: anteroposterior height, radial-ulnar width, and radius of curvature. Measurements were obtained from posteroanterior and lateral radiographic views, which were digitized and analyzed using digital imaging software. Comparable measurements were obtained from the base of the small and ring metacarpals. RESULTS: The anteroposterior dimension of both potential donor metacarpals was large enough to resurface the distal condyles of each of the proximal phalanges; however, this was not true for the radial-ulnar dimensions. The distal ulnar condyle of the long finger proximal phalanx was largest, measuring 4.9 (+/- 0.) mm dorsally and 6.2 (+/- 0.5) mm volarly in the radial-ulnar dimension. Only the small metacarpal base had sufficient stock in the radial-ulnar dimension (9.4 [+/- 1.7]) mm dorsally and 10.6 [+/- 2.0] mm volarly) to resurface this condyle. With respect to radius of curvature (ROC), the donor-to-recipient ROC ratio was 1.43 for the small metacarpal base versus 2.12 for the ring metacarpal base. Linear regression analysis revealed a stronger relationship in ROC between donor and recipient condyle when the small metacarpal base served as the donor (R = 0.96 vs R = 0.60). CONCLUSIONS: As determined from morphometric measurements of the 2 potential donor sites tested, the base of the small metacarpal provides the best match for resurfacing distal condylar defects of the proximal phalanges.

Paraesophageal hiatal hernia. Open vs. laparoscopic surgery.

BACKGROUND: paraesophageal hiatal hernia represents 5-10% of hiatal hernias. Its importance is based on the severe complications it may have, including gastric volvulus, and surgical treatment is recommended when a diagnosis is established. MATERIAL AND METHODS: a retrospective study of all patients who underwent surgery for paresophageal hernia between 1985 and 2007. RESULTS: we studied 90 cases, 68 females and 22 males with a median age of 67.6 years (37-96). Forty-five patients reported pyrosis, 34 epigastric postprandial pain, and 15 dysphagia; eight patients were diagnosed with gastric volvulus. Eighty-one patients underwent elective surgery and 9 emergency surgery. Forty-seven cases underwent an open procedure and 43 a laparoscopic one; 5 (11.6%) of them required conversion. The techniques performed were D Or fundoplication in 35 cases, Nissen in 35, Toupet in 14, simple hiatal closure in 2, Narbona in 1, and Lortat-Jakob in 1; in 10 patients a mesh was placed. The complication rate for open procedure was 10.6 and 9.5% for the laparoscopic one (p > 0.05). Median hospital stay was 9.1 days for the open procedure and 3.4 for the laparoscopic one (p < 0.05). As follow-up, we analyzed 84 patients. After a median follow-up of 12 years (1-19), 15 patients were still symptomatic (17.8%), with recurrence in 8 cases (5 required reoperation). The satisfaction rate was 95.5%. CONCLUSION: equivalent results were observed after laparoscopic and open surgery and a significant shorter hospital stay in the laparoscopic one. Therefore, we think that laparoscopic surgery should be considered as the election procedure for paraesophageal hiatal hernia.

Galectin-1 induces nuclear translocation of endonuclease G in caspase- and cytochrome c-independent T cell death.

Galectin-1, a mammalian lectin expressed in many tissues, induces death of diverse cell types, including lymphocytes and tumor cells. The galectin-1 T cell death pathway is novel and distinct from other death pathways, including those initiated by Fas and corticosteroids. We have found that galectin-1 binding to human T cell lines triggered rapid translocation of endonuclease G from mitochondria to nuclei. However, endonuclease G nuclear translocation occurred without cytochrome c release from mitochondria, without nuclear translocation of apoptosis-inducing factor, and prior to loss of mitochondrial membrane potential. Galectin-1 treatment did not result in caspase activation, nor was death blocked by caspase inhibitors. However, galectin-1 cell death was inhibited by intracellular expression of galectin-3, and galectin-3 expression inhibited the eventual loss of mitochondrial membrane potential. Galectin-1-induced cell death proceeds via a caspase-independent pathway that involves a unique pattern of mitochondrial events, and different galectin family members can coordinately regulate susceptibility to cell death.

The benefits of stereoscopic vision in robotic-assisted performance on bench models.

BACKGROUND: Previous studies have failed to establish clear advantages for the use of stereoscopic visualization systems in minimal-access surgery. The aim of this study was to objectively assess whether stereoscopic visualization improves performance on bench models using the da Vinci robotic system. METHODS: Eleven surgeons carried out a series of four tasks. Positional data streamed from the da Vinci system was analyzed by means of a previously validated custom-designed software-package. An independent blinded observer scored errors. Statistical analysis included the Wilcoxon signed rank test. A p < 0.05 was deemed significant. RESULTS: We found significant improvements in all tasks and for all parameters (p < 0.05). In addition, a significantly lower number of errors was scored using the stereoscopic mode as compared to the standard two-dimensional image (p < 0.001). CONCLUSION: Robotic-assisted performance on bench models is more efficient and accurate using stereoscopic visualization.

Qualitative and quantitative analysis of the learning curve of a simulated surgical task on the da Vinci system.

BACKGROUND: Robotic telemanipulation systems provide solutions to the problems of less dexterity and visual constraints of minimally invasive surgery (MIS). However, their influence over surgeons' dexterity and learning curve needs to be assessed. We present motion analysis as an objective method to measure performance and learning progress.METHODS. Thirteen surgeons completed five synthetic small bowel anastomoses using the da Vinci system. Objective Structured Assessment of Technical Skills (OSATS) allowed qualitative analysis. Quantitative analysis used API software of the system to retrieve real-time robotic signal data of time, path length, and number of movements. Wilcoxon signed ranks test was used for statistical analysis. A p value <0.05 was considered significant.RESULTS. OSATS global scores were 18.6 points for the first attempt and 26 for the fifth attempt ( p < 0.02, Cronbach's alpha = 0.894). Paired data of motion analysis for attempts 1 vs 5 showed significant change: time taken 3507 sec and 2287 sec ( p < 0.008), total number of movements 2411 and 1387 ( p = 0.01), total path length 21,630 cm and 13,941 cm ( p = 0.01).CONCLUSIONS. A rapid learning curve to a competent level using the da Vinci system is possible aided by the system's intuitive motion. Motion analysis is a useful tool to measure performance in the da Vinci system compared to OSATS and time alone.

Estudio y tratamiento racionales de la vía biliar en pancreatitis aguda / Rational study and treatment of biliary duct in acute pancreatitis

Se presenta el estudio y tratamiento de la via biliar en 67 pacientes con pancreatitis aguda y patologia biliar asociada. La colangiopancreatografia retrograda endoscopica (CPRE), tuvo las siguientes indicaciones : I. Temprana urgente, cuando el episodio fue considerado grave al ingreso y se acompanaña de signos de obstruction biliar o colangitis (n=2). II. Tardia urgente, cuando el episodio al ingreso era considerado leve, pero evolucionaba rápidamente y presentaba signos de obstruccion biliar o colangitis ( n=3 ). III. Electiva, cuando el episodio era leve y de recuperacion rápida pero habia signos de obstruccion biliar persistente (n= 12). Si el episodio era leve y sin ningun signo que indicara obstruccion biliar persistente o colangitis, los pacientes eran llevados a colecistectomia y colangiografia intraoperatoria ( CIO ) (n= 40) La gravedad se estimo con APACHE II. La coledocolitiasis estuvo presente solamente en 9 casos ( 13,4 por ciento). La CIO fue normal en los 40 casos que se realizó. La mortalidad en general fue de 8 casos (12 por ciento) pero solamente 4 murieron por causa directa de la pancreatitis (6 por ciento). Conclusion: La CPRE en pancreatitis aguda biliar debe ser usada en forma selectiva, ya que tiene indicaciones precisas; la CIO es de mucho valor en pacientes en quienes no está indicada la CPRE; la colangiopancreatografia por resonancia magnetica (CPRM) y la ultrasonografia endoscopica ( UE) no están al alcance de nuestras manos; sin embargo, señalamos que no son terapeuticas pero si muy costosas.

Clinical recognition and management of pediatric blunt abdominal trauma without ultrasound or computed tomography scan in community hospitals in Mexico.

PURPOSE: The aim of this study was to characterize the evaluation and clinical course of children with blunt abdominal trauma in second-level hospitals. METHODS: The authors reviewed the medical records of children, age 1 to 17 years, admitted with blunt abdominal trauma between the years 1988 to 1998. The initial evaluation included a Pediatric Trauma Score (PTS) ABCD clinical assessment, resuscitation, diagnostic peritoneal lavage (DPL), Glasgow Coma Scale (GCS), x-ray, and laboratory values. Surgical indications included active bleeding, perforated hollow viscus, or traumatic diaphragmatic hernia. Sixty-four children with blunt abdominal trauma were divided into 4 major groups: group I, obtunded children who required abdominal surgery; group II, obtunded children that did not require abdominal surgery; group III, responsive children that required abdominal surgery; group IV, responsive children that did not require abdominal surgery. RESULTS: Analyses of each group determined that the PTS, the GCS, and ABCD assessments accurately reflected the degree of injury and outcome. Jointly with DPL they may obviate the need of ultrasound and CT scan in hospitals of second level that do not have access to these resources. CONCLUSIONS: Recognition of blunt abdominal trauma in children may be complicated by associated multisystem injury. Systematic evaluation minimizes missed diagnosis and facilitates rapid and effective treatment. The benefit of data acquired from a good ABCD assessment, PTS, GCS, clinical and radiological, and DPL evaluation, facilitates the decision to conduct a rapid laparotomy, and they help to predict the outcome of this kind of patient.

Expression of bone morphogenetic protein-7 mRNA in normal and ischemic adult rat kidney.

BMP-7, a member of the bone morphogenic protein subfamily (BMPs) of the transforming growth factor-beta superfamily of secreted growth factors, is abundantly expressed in the fetal kidney. The precise role of this protein in renal physiology or pathology is unknown. A cDNA that encodes rat BMP-7 was cloned and used as a probe to localize BMP-7 mRNA expression by in situ hybridization in the adult rat kidney. The highest expression of BMP-7 mRNA could be seen in tubules of the outer medulla. In glomeruli, a few cells, mainly located at the periphery of the glomerular tuft, showed specific and strong signals. Also, high BMP-7 mRNA expression could be localized to the adventitia of renal arteries, as well as to the epithelial cell layer of the renal pelvis and the ureter. Preliminary evidence suggests that BMP-7 enhances recovery when infused into rats with ischemia-induced acute renal failure. We examined BMP-7 mRNA expression in kidneys with acute renal failure induced by unilateral renal artery clamping. BMP-7 mRNA abundance as analyzed by solution hybridization was reduced in ischemic kidneys after 6 and 16 h of reperfusion compared with the contralateral kidney. In situ hybridization in ischemic kidneys showed a marked decrease of BMP-7 mRNA in the outer medulla and in glomeruli. Utilizing rat metanephric mesenchymal cells in culture, we also demonstrate that BMP-7 induces epithelial cell differentiation. Taken together, these data suggest that BMP-7 is important in both stimulating and maintaining a healthy differentiated epithelial cell phenotype.

Shiga toxin 1 elicits diverse biologic responses in mesangial cells.

BACKGROUND: Shiga toxin 1 (Stx1) is a causative agent in hemolytic uremic syndrome (HUS). Its receptor, the glycosphingolipid globotriaosylceramide (Gb3), is expressed on cultured human endothelial and mesangial cells. Mesangial cell injury in HUS ranges from mild cellular edema to severe mesangiolysis and eventual glomerulosclerosis. We hypothesized that, in addition to endothelial cells, mesangial cells are targets of Stx1. METHODS: Human mesangial cells were exposed to Stx1. Protein synthesis was measured using [35S]-methionine/cysteine. Cell viability was measured as the lysosomal uptake of Neutral Red. Monocyte chemotactic peptide (MCP-1) mRNA and protein were analyzed by Northern blotting and ELISA. RESULTS: Stx1 (0.25 to 2500 ng/ml) resulted in a dose-dependent inhibition of protein synthesis. This effect of Stx1 was potentiated by preincubation of the cells with interleukin-1alpha (IL-1alpha; 2 ng/ml) or tumor necrosis-alpha (TNF-alpha; 500 U/ml). Stx1 had little effect on mesangial cell viability during the first 24 hours of exposure to Stx1. However, prolonged incubation with Stx1 for 48 and 72 hours resulted in a 68% and 80% decrease in cell-viability, respectively. Stx1 elicited a dose and time dependent increase in the levels of MCP-1 mRNA, an effect that was potentiated by preincubation with IL-1alpha. CONCLUSION: These data indicate that mesangial cells are susceptible to the effects of Stx1 in vitro. Stx1 exerts a spectrum of biologic effects on mesangial cells ranging from activation of chemokine genes to a lethal toxic injury. Immunoinflammatory cytokines potentiate the effects of Stx1. Thus, glomerular pathology in HUS may also result from a direct effect of Stx1 on mesangial cells.

Vestibular nerve regeneration in the bullfrog, Rana catesbeiana: peripheral dendrites.

Three experiments were conducted on healthy adult bullfrogs (Rana catesbeiana) for the purpose of investigating three characteristics of centrifugal vestibular afferent regeneration after complete transection of the anterior division of the vestibular nerve (AVN). In experiment 1 total fiber count and axon diameter measurements were obtained from the anterior canal nerve at three different time periods and compared with normal. The normal group (n = 3) demonstrated a total fiber count of 1001 +/- 76 (SEM). The early time period (1 to 2 weeks, n = 3) did not completely regenerate as demonstrated by a total fiber count of 282 +/- 23. The intermediate (4 to 6 weeks, n = 3) and late (8 to 16 weeks, n = 3) groups exhibited total fiber counts of 907 +/- 29 and 946 +/- 50, respectively, which were not different from normal (Mann-Whitney U, p > 0.2). Evaluation of fiber diameter distribution of the intermediate and late regenerated nerves revealed a reduction in axon diameter caliber compared with normal (analysis of variance, p < 0.0001). Thus transection of the AVN results in regeneration of all afferents that exhibit a reduction in axon diameter. In experiment 2 fibers innervating the anterior canal crista (ACC) were prelabeled before nerve transection. After the labeling procedure the AVN (n = 3) was sectioned at a location that resulted in denervation of three vestibular receptors: the ACC, horizontal canal cristae (HCC), and utricular macula. After 4 weeks of regeneration the ACC fibers that were prelabeled were observed innervating all three denervated vestibular receptors. This result demonstrated that reinnervation of the peripheral vestibular end organs after AVN transection is a nonspecific process. In experiment 3, 167 regenerated canal afferents were evaluated for functional recovery 16 weeks after transection. Both spontaneous and rotation-induced discharge characteristics were obtained and compared with those obtained from a sample of 254 normal afferents in a previous study (Hoffman LF. Factors affecting the response dynamics of canalicular primary afferent neurons in the bullfrog. St. Petersburg (FL): Association for Research in Otolaryngology; 1989). The mean spontaneous discharge coefficient of variation (CV) +/- standard deviation was 0.60 +/- 0.32 and 0.49 +/- 0.33 for ACC and HCC regenerated afferents, respectively, which did not differ from the normal means of 0.63 +/- 0.33 and 0.54 +/- 0.36 (Mann-Whitney, p > 0.2). Response gains and phases obtained during 0.05 Hz sinusoid rotations at 15 degrees/second maximum horizontal table velocity also demonstrated normal discharge characteristics. The mean phases were -28.2 +/- 25.2 degrees and -55.9 +/- 21.5 degrees for regenerated ACC and HCC afferents, respectively, which were not different from the normal means of -33.77 +/- 24.31 degrees and -58.0 +/- 23.3 degrees (Mann-Whitney U). Furthermore, regenerated afferents exhibited a positive association between phase and CV, which was also true for normal afferents (correlation analysis, p > 0.001). Although the mean gains for regenerated ACC and HCC (7.13 +/- 5.5 and 3.3 +/- 2.4 spikes x sec(-1)/degrees x sec(-2), respectively) afferents were reduced from normal ACC and HCC (14.8 +/- 12.52 and 7.76 +/- 6.58 spikes x sec(-1)/degrees x sec(-2), respectively) afferents (Mann-Whitney U, p > 0.0001), a positive association between gain and CV was also demonstrated by regenerated afferents, as was the case for normal afferents (correlation analysis, p < 0.001). Thus the overall response discharges of regenerated afferents were comparable with normal afferents. Normally, large fibers innervate central regions of the receptor, and smaller fibers innervate the peripheral regions. However, the data from experiments 1 and 2 demonstrate that vestibular nerve regeneration results in a dissociation between the normal topographic organization of fiber size and regional innervation of the receptor epithelium. (ABSTRACT TRUNCATED)

Profilaxis antibiótica en cirugía laparoscópica: sus indicaciones / Antiobiotic prophylaxis in laparoscopic surgery

Desde hace mucho tiempo se ha reconocido la importancia de la profilaxis antibiótica en cirugia, y es claro su beneficio en las heridas limpias, pero el tema no se ha discutido ampliamente en el campo de la cirugia minimamente invasora, y solo existe alguna informacion en cuanto a la colecistectomia laparoscopica. Se presenta una revision de los conocimientos actuales que permiten entender el proceso de la colonizacion bacteriana y la posterior infeccion de la herida quirurgica y la forma de intervenirlo. Se hace enfasis en las diferencias entre la cirugia convencional y la cirugia laparoscopica y se dan las recomendaciones para la cirugia minimamente invasora, que a la luz de los conocimientos actuales tiene menor riesgo de infeccion.

Esplenectomía laparoscópica / Laparoscopic splenectomy

Se presenta la experiencia de los autores en esplenectomia laparoscopica a partir de 1994, en la que se describe por primera vez en el pais la práctica de 29 casos en pacientes con purpura trombocitopenica idiopatica, esferocitosis hereditaria y anemia hemolitica autoinmune. Se discuten las indicaciones y contraindicaciones, se describe la tecnica quirurgica y las variaciones que hemos implementado, comparándolas con las de otros autores, con el fin de disminuir costos. Se presentan los resultados y se concluye que es un procedimiento seguro, eficaz, con las ventajas para el paciente de la cirugia minimamente invasora, y que es posible realizarlo a costos razonables.

Amebic hepatic abscess in children.

The authors retrospectively reviewed all case histories of children with amebic hepatic abscess treated from 1975 to 1993 at their hospital. Twenty boys and 12 girls were diagnosed. Their ages ranged from 10 months to 12 years, with a mode of 1 and 2 years. In 17 (53%) of the patients, the abscess remained confined to the liver and was treated medically with dehydroemetine and metronidazole. Imminence of complication was present in 9 patients (52%), and required percutaneous needle aspiration. Imminence of complication was evidenced by: (1) clinical worsening of the patient despite adequate medical treatment, (2) presence of an abscess of 6 cm or more in a septic patient, or (3) clinical or ultrasonographic findings of an abscess on the verge of rupture. All 9 patients did satisfactorily. Fifteen cases (47%) were complicated by rupture and required surgical treatment. One of these patients died of sepsis. Medical treatment alone was excellent for small abscesses. Percutaneous needle aspiration was a successful approach in patients with imminence of complication. Surgery was reserved for ruptured abscesses.

[Prenatal ultrasonographic diagnosis and early surgical treatment in choledochal cyst]. / Diagnóstico ultrasonográfico prenatal y tratamiento quirúrgico precoz en quiste de colédoco.

The clinical case of a 23 days old male newborn with prenatal ultrasonographic diagnosis of choledochal cyst is described and discussed. The diagnosis was first suspected in the 23rd gestation week and confirmed in the 35th. The advantages of prenatal ultrasonographic diagnosis and early surgical management in patients with choledochal cyst are emphasized.