Monitoring volatile compounds production throughout fermentation by Saccharomyces and non-Saccharomyces strains using headspace sorptive extraction.

Currently, there is a growing interest in the use of non-Saccharomyces yeast to enhance the aromatic quality of wine, with pure or mixed cultures, as well as sequential inoculation. Volatile components of wines were closely related to their sensory quality. Hence, to study the evolution of volatile compounds during fermentation was of great interest. For this, sampling methods that did not alter the volume of fermentation media were the most suitable. This work reports the usefulness of headspace sorptive extraction as non-invasive method to monitor the changes in volatile compounds during fermentation. This method allowed monitoring of 141 compounds throughout the process of fermentation by Saccharomyces cerevisiae and Lachancea thermotolerans strains. Both strains showed a similar ability to ferment a must with high sugar content. The S. cerevisiae strain produced higher amount of volatile compounds especially esters that constitutes fruity aroma than L. thermotorelans.

Latitudinal prevalence gradient of multiple sclerosis in Latin America.

BACKGROUND: Multiple sclerosis (MS) has a unique geographical distribution that reflects both genetic and environmental factors. Many studies have shown a positive correlation between MS frequency and latitude across both large and small geographical regions. However, scarce data have been published on the epidemiology of MS in Latin America and no study has evaluated latitudinal variation. OBJECTIVE: To evaluate the effect of latitude on MS prevalence in Latin America. METHODS: We conducted a systematic review of MS prevalence during January 2011. Prevalence rates were collected from eligible publications. The effect of latitude on prevalence was analyzed using linear regression. RESULTS: A total of ten studies were eligible for analysis, corresponding to six countries, spanning from Panama to Argentina. The crude prevalence of MS ranged from 0.75 to 21.5 per 100,000. We found a strong and significant association between prevalence and latitude (r(2) 0.8; p < 0.001) and determined an increase in prevalence of 0.33 per 100,000 per degree latitude. CONCLUSION: Our findings suggest a latitudinal prevalence gradient of MS in Latin American countries between Panama and Argentina.

Influence of Saccharomyces cerevisiae and Lachancea thermotolerans co-inoculation on volatile profile in fermentations of a must with a high sugar content.

The aim of this work was to evaluate how the use of mixed cultures of Saccharomyces cerevisiae and Lachancea thermotolerans indigenous yeast strains influences the volatile composition of wine. Multivariate curve resolution (MCR) method has been applied to data analysis. Five fermentation trials were carried out: three co-inoculated with L. thermotolerans:S. cerevisiae, at the ratio of 50:1, 20:1 and 5:1 respectively, and two with a pure culture of each strain. A must from sun-dried Pedro Ximénez grapes was employed. Volatile composition was determined by dual sequential stir bar sorptive extraction, followed by GC-MS analysis. MCR provided 171 peaks. Results in co-inoculation fermentations revealed that the majority compounds obtained in each case followed the same trend as that observed for the pure culture of the strain that was present in a higher proportion. Finally, 50:1 and 20:1 seemed to be the best proportions to obtain a wine with a quality volatile profile.

Ocular microcirculation. Scanning electron microscopic study.

A simple vascular casting technique utilizing a low-viscosity plastic was used to study the three-dimensional ocular microcirculation of the cat eye. Vascular arrangements in different anatomic areas of the eye, i.e., iris, ciliary body, retina, optic nerve, and choroid, were clearly elucidated by scanning electron microscopy. This modified technique is described in detail, and scanning electron micrographs are presented to illustrate the reliable results.

Choroidal microvascular repair after argon laser photocoagulation. Ultrastructural observations.

Acute laser injury to the tapetum of the feline retina produces thrombosis of the choriocapillaris. Early changes are characterized by the appearance of platelet-fibrin thrombi within capillary loops and disruption of endothelial integrity. By 4 days, thrombi have disappeared, and the endothelium shows regenerative changes. No endothelial cell mitotic activity is seen. The endothelial cytoplasm becomes plump, and there is a loss of the fenestrations adjacent to Bruch's membrane. By 10-20 days, the capillary structure shows gradual restoration. At 30 days, endothelial cell fenestrae are clearly evident adjacent to Bruch's membrane. The reparative process in this model appears to evolve as a result of thrombolysis and endothelial cell activation.

Angioarchitecture of the ciliary artery circulation of the posterior pole.

Morphologic findings on scanning electron microscopy of vascular cast of the posterior pole in primates are presented. The prelaminar region of the optic disc received the majority of its blood supply from the short posterior ciliary arteries, mainly from direct branches arising from peripapillary arterioles surrounding the optic nerve but also from indirect branches from the peripapillary choroid. The capillaries from this prelaminar region drained directly into the central retinal vein. The peripapillary choriocapillaris was a single layer of anastomosing capillaries supplied by precapillary choroidal arterioles. The peripapillary choriocapillaris was not seen to contribute to the vascular supply of the optic disc. Our results are in general agreement with those of previous scanning electron microscopy studies of the vascular supply of the distal part of the optic nerve.

Observations on the microvascular repair process after confluent argon laser photocoagulation.

We observed the repair process of the choriocapillaris after confluent argon laser retinal photocoagulation in the domestic cat with a plastic injection-corrosion technique coupled with scanning electron microscopy and transmission electron microscopy. Confluent photocoagulation was applied to the area of the retinal tapetum, creating two kinds of lesions: one consisted of five confluent burns and the other of 20 confluent burns. Specimens were prepared at 1, 30, and 60 days. Occlusion of the choriocapillaris was noted regardless of the length of time after photocoagulation. The only sign of repair was noted at 60 days when the choriocapillaris located at the edge of the lesion showed a uniform rearrangement. Transmission electron microscopy revealed severe damage to the endothelial cells, with lack of cell activation and permanent capillary closure in the vessels of the lesion proper.

Choroidal microvascular repair after argon laser photocoagulation.

We studied the repair process of the choriocapillaris after argon laser retinal photocoagulation in the domestic cat with a plastic injection-corrosion technique and scanning electron microscopy. Retinal scatter photocoagulation was applied to the tapetum at threshold-, moderate-, and high-intensity levels and specimens prepared one, ten, and 30 days later. At 24 hours after photocoagulation, obstruction of the choriocapillaris was always present regardless of the power used. In lesions produced by higher-intensity energy levels, choriocapillaris defects had larger diameters and larger vessels were affected more severely. At ten days, there were early signs of choriocapillaris repair. At 30 days, choriocapillaris occupied almost the entire area of the defect, although the normal lobular architecture was not present.

Photorefractive keratectomy after radial keratotomy.

BACKGROUND: Twenty-three eyes of 22 patients remained undercorrected 5 to 49 months after radial keratotomy, either alone or in combination with transverse keratotomy. METHOD: We attempted to correct the residual myopia ranging from -1.25 to -5.75 diopters (D) (with astigmatism of 0 to 1.25 D) with photorefractive keratectomy. The mean age of patients was 26 years (range 22 to 40 years). RESULTS: After photorefractive keratectomy (follow-up 6 to 17 months) uncorrected visual acuity was equal to or better than 20/20 in 39% (9 eyes), better than 20/25 in 65% (15 eyes), and better than 20/40 in 74% (17 eyes). Spectacle-corrected visual acuity was equal or better than 20/40 in all eyes; one eye (4%) lost two lines of spectacle-corrected visual acuity. Refractive error was within +/- 0.50 D in 48% (11 eyes) and within +/- 1.00 D in 65% (15 eyes). Undercorrections of more than 1.00 D occurred in 22% (5 eyes) and overcorrections of more than 1.00 D occurred in 13% (3 eyes). No or minimal haze was present in 57% (13 eyes), mild haze in 39% (9 eyes) and moderate haze in 4% (1 eye). Final uncorrected visual acuity was better (p = 0.0002) and haze was less (p = 0.003) in the group with less than -3.00 D than in the group with greater than or equal to -3.00 D. CONCLUSION: Photorefractive keratectomy after radial keratotomy is safe but less effective and less predictable in eyes with greater than or equal to -3.00 D compared to those with less than -3.00 D.

A case of corneal keloid: clinical, surgical, pathological, and ultrastructural characteristics.

A 69-year-old patient developed a localised, whitish, elevated, corneal lesion with a smooth and glistening surface following trauma, without evidence of corneal perforation. Twelve months later, the lesion showed evidence of slow growth. An excisional biopsy was then performed. Histopathologically, the lesion was covered by non-keratinised squamous epithelium and was comprised of randomly oriented collagen fibres containing active fibroblasts. Blood vessels were noted deep in the lesion. Ultrastructurally, the cell population was formed by fibroblasts and myofibroblasts, similar to keloids of the skin. The clinical, pathological, and ultrastructural features of the corneal lesion are compatible with a corneal keloid.

Characteristics and repercussion of varicella-zoster virus infection in cardiac transplant.

Generally, the need for information about varicella-zoster virus (VVZ) infection in cardiac transplantation (CT) is greater than that for other organ transplants. All cases of VVZ infection among the 175 CT patients included herpes zoster as the clinical syndrome in all 11 cases (men, 90.9%; mean age, 50.3+/-5 years; incidence, 6.3%). The infection was limited to one dermatome in seven patients (63.6%: thoracic, 6%; ophthalmic, 1), or two contiguous dermatomes in four patients (36.4%). The infection onset was after the first semester in seven patients (63.6%). All patients received three drug immunosuppressive therapy. Cardiac rejection during the three previous months occurred in one patient (3A grade). Previous CMV disease was observed in three patients (27.3%: range, 7-14 months). Intravenous acyclovir was administered to five patients (ophthalmic and several dermatome forms), and oral therapy for the rest. All the patients recovered; there were no complications or postherpetic neuralgia (mean follow-up: 16.5 months). VVZ infection, a frequent late infection among CT recipients, presents as a clinical syndrome of herpes zoster, frequently in patients with previous CMV infection. In CT, herpes zoster frequently affects two dermatomes, but the clinical courses and responses to treatment are favorable. There was no postherpetic neuralgia.

Endophthalmitis cluster from contaminated donor corneas following penetrating keratoplasty.

OBJECTIVE: To attempt to identify common events or factors in four cases of endophthalmitis that developed after penetrating keratoplasty performed within a 1-week interval. DESIGN: Case series. SETTING: Tertiary care eye hospital in Riyadh, Saudi Arabia. PATIENTS: Four patients in whom endophthalmitis developed after penetrating keratoplasty performed in May 1993. OUTCOME MEASURES: Source of donor tissue, transportation of corneas, handling of corneas at the eye hospital, and causative organism and sensitivity profile. RESULTS: The donor tissue in all four cases originated from the same eye bank. Organisms were cultured from 10 of the 11 donor rims from eye bank A tissue used during the week in question. The causative organisms were Enterococcus faecalis in three patients and Torulopsis glabrata in one patient. In each case the same organism was cultured from the recipient eye and the corresponding donor rim. Two of the four patients had a favourable outcome. CONCLUSIONS: Donor rim culture is essential if the cause of endophthalmitis after penetrating keratoplasty is to be determined. Close communication between eye bank personnel, the microbiology laboratory and the operating surgeon is important as it may influence early detection, choice of treatment and outcome of endophthalmitis after penetrating keratoplasty. Epidemiologic studies from both the source eye bank and the recipient facility are required to fully investigate the cause of a cluster of endophthalmitis cases from contaminated donor tissue following penetrating keratoplasty.

Bilateral macular infaction in SS disease.

A 10-year-old Afro-American female with SS disease presented with a history of painless loss of vision (RE) of 26 hours duration. Sequential fluorescein angiography revealed bilateral parafoveal occlusions and evidence of prior vaso-occlusions in each eye. Initial hydration therapy with dextrose 5% and 1/4 normal saline was followed within eight hours by transfusion with two units of packed red blood cells. Patency was restored to the occluded arterioles with return of normal acuity in LE, though the vision remains at hand motions in the RE. Sudden loss of central acuity in sickle hemoglobinopathies may result from vaso-occlusion in terminal arterioles near the foveal avascular zone. Therefore a reduced number of permanently irreversibly sickled red blood cells may prevent these macular infarcts.

A comparison of nurse anesthesia practice types.

The present study examined the differences between anesthesia care team (ACT) and non-ACT practice types. Six practice variables were analyzed. We prepared and distributed a 13-item questionnaire to 1,000 practicing Certified Registered Nurse Anesthetists (CRNAs) with a 44.4% response rate. Data analysis revealed that nurse anesthetists in ACT practices had fewer years of experience and were younger than non-ACT nurse anesthetists (alpha = 0.05). Also, a significantly greater percentage of ACT nurse anesthetists were female, held master-level degrees, and practiced in urban and metropolitan locations. This also was true for placement of laryngeal mask airways and arterial lines, and in providing anesthesia for cardiopulmonary bypass, pediatric, intracranial, and trauma cases. However, a significantly greater percentage of non-ACT nurse anesthetists placed epidurals and central lines and were involved in pain management and critical care consultations. Income was significantly greater for non-ACT nurse anesthetists as well, but they worked more hours per week on average. Lastly, evaluation of employment arrangements showed that more than 91% (n = 361) of ACT nurse anesthetists were employees, and only 4% (n = 17) were self-employed. However, only 49% (n = 24) of non-ACT nurse anesthetists were employees, and almost 43% (n = 21) were self-employed. The present study demonstrates that significant differences exist between the 2 nurse anesthesia practice types examined. As nurse anesthesia practice arrangements continue to change and fewer CRNAs are hospital employed, each nurse anesthetist must be aware of current practice trends and understand the alternatives.

[Eosinophilia in pediatrics. Report of clinical cases]. / Eosinofilia en pediatría. Presentación de casos clínicos.

We present four clinical cases where eosinophilia was a prominent sign. Final Diagnoses were Toxocariasis, Ascaris Lumbricoides Infection, Acute Lymphocytic Leukaemia and Histiocytosis of Langerhans Cells.

[Submaxillary sialolithiasis due to Actinomyces israelii. A case report]. / Sialolitiasis submaxilar por actionomices Israelii. A propósito de un caso.

Actynomicosis of the submaxillary gland is a very uncommon infectious disease. In this article one case of submaxillary sialolithiasis by actynomices israelii in a young girl is presented. We discuss several aspects of its diagnosis and therapeutic possibilities and review the literature on the subject. We emphasize the interest and value of performing a microbacteriological, mineralogical and pathological study of the calculi.

[In-depth study of the causes of sudden deafness. Physiopathological mechanisms and their reversal]. / Profundizando en las causas de la hipoacusia súbita. Mecanismos fisiopatológicos y de reversión.

This article deals with an investigative work done by the AA. with the aim of determine the final cause of sudden sensorial deafness. Three causes are accepted as source of sudden deafness: viral infections, the tear away of labyrinthine membranes and the vascular theory. An increase in antibody titer suggest a viral origin. The labyrinthine membranes split has been observed at times when performing an exploratory tympanotomy. But circulatory troubles are hardly diagnosed, even with histopathological evidences of vascular upsets in temporal bones belonging to patients who suffered from an auditory stroke, because there are no diagnostic tests for "in vivo" control. Our intend is to investigate on the physiopathology of unforeseen deafness and also try to know the possible mechanisms of reversion of this calamitous pathology. We use, as investigative method of actual vascular changes in sudden deafness, the following; the speed analysis of the blood flow furnished by the A. labyrinthi through echography Doppler color transcranialis and angiography and magnetic resonance (Angio-MR). Both procedures are non invasive and harmless. We comment the findings of 13 patients. And find out, in 4 cases, an important trouble of the arterial vertebrobasilaris flow. The A. labyrinthi, a branch of the A. cerebelli inferior anterior (ACIA) and/or A. basilaris--rarely from the A. cerebelli inferior posterior (ACIP)--showed a heavy hypoplasy of these vessels, stenosis or complete blockage. In 2 of cases, 4 months later, a new exploration of the Doppler flow and angio-MR, was performed, and detected an improvement of the vertebrobasilar flow, in both instances. In those patients with an evident recovery of the hearing, it was attributed to these two compensatory mechanisms: 1) reversal of the flow at the level of cicle of Willis, at the expense of development of A. communicans posterior, and 2) cessation of the vertebral A. spasm and decrease of the vessel's tortuosity so improving the blood flow.

[Mikulicz disease as the beginning of AIDS]. / Enfermedad de Mikulicz como debut en un caso de SIDA.

Major salivary lymphoepithelial lesions accounted for less than 3 percent of all benign parotid tumors, prior to AIDS acquaintance. Defined as the presence of enlargement of one or more salivary glands and, in some cases, with diminished salivary function. The paper present the case of an acquired immunodeficiency syndrome starting as a Mikulicz's disease. Reviewed the medical literature and treatment options.

[Treatment and outcome of infantile cholesteatoma surgery]. / Tratamiento y resultados en la cirugia del colesteatoma infantil.

Infantile Cholesteatoma has been lately the aim of a large number of papers dealing with its natural history and optimal treatment. The outcome of 26 cases of ear surgery, done between 1990 and 1991, are reviewed. The etiology of Cholesteatoma was congenital in 2 cases, iatrogenic in an other one and unknown for the remainder (88%). Fifteen (15) closed surgical procedures and 11 open were carry out, achieving global removal of lesions in 76 percent of cases. Ninety-one (91%) of open tympanoplasties and 66 percent of closed procedures. Six cases evolved to recidivation (and later reoperatively reconverted in open cases) owing either to the erosion of the ossicular chain or encroachment of the recessus. Reconstructions of the ossicular chain was undertaken in 61.5 percent of cases and the hearing preserved in all instances and improved in 35 percent of reconstructions.

[Otoneurological manifestations of basilar dolicoectasia. A report of six cases]. / Manifestaciones otoneurológicas de la dolicoectasia basilar. A propósito de seis casos.

Megadolichobasilar is a vascular anomaly consisting of widening and elongation of the basilar artery. It is rare and may produce otoneurological manifestations such as vertigo, sudden deafness, trigeminal neuralgia, and facial spasm or palsy. Six cases of megadolichobasilar diagnosed by magnetic resonance angiography are reported and their pathogenesis is discussed.