3D CT stereoscopic imaging: observations of the frontal and anterior ethmoid sinuses development from birth to early adulthood

Objective: Our objective is to provide observations demonstrated with 3Dimensional Computed x-ray Stereoscopic Imaging (3DCTSI) in the evaluation of the anterior ethmoid and frontal sinus development from birth to age 18. Methods: This is a retrospective evaluation of patient’s CT studies performed over a fifteen-year period, reported as normal studies, and included 53 patients (142 sides) from birth to age 18. Results: At birth, there are two spaces covered by folds, the uncinate and bulla lamellae. The spaces communicate with the Middle Meatus (MM) through the emerging ethmoid infundibulum (EI) and the retrobulbar recess space (RBRS). In the first month after birth, an expansile and breakdown developmental phase blend and continue throughout the growth into the teenage years. The 3D images reveal dark lamellar structures, on the surface of the medial lamina papyracea as well as bridging the broken spatial outlines. The dark lamellae represent the mucosal lamina propria, in unossified lamellae and are the origin of permanent spatial walls. From ages 4 to 18 years, initially, the frontal recess (FR) and later the MM penetrate into the cancellous frontal bone creating the frontal Sinus (FS), the frontal septum (FS), Inter-Frontal Sinus Septal Cell (IFSSC), as well as the Fronto-Ethmoidal and Frontal Bulla Spaces. Conclusion: 3DCTSI is the first intuitive imaging modality to reveal the microanatomical development of the anterior ethmoid and frontal sinus anatomy.

First case of within-host co-infection of different SARS-CoV-2 variants in Ecuador

Background

COVID-19 infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause mild symptoms to severe illness and death. Co-infections of SARS-CoV-2 with other respiratory viruses have been described. However, two SARS-CoV-2 lineage co-infection have been rarely reported.

Methodology

A genotyping analysis and two different types of whole genome sequencing were performed (Illumina MiniSeq and ONT MinION). When examining the phylogenetic analysis in NextClade and Pangolin webservers, and considering the genotyping findings, conflicting results were obtained.

Results

The raw data of the sequencing was analyzed, and nucleotide variants were identified between different reads of the virus genome. B.1 and P.1 lineages were identified within the same sample.

Conclusions

We concluded that this is a co-infection case with two SARS-CoV-2 lineages, the first one reported in Ecuador.

Cadaveric Classification of the Genicular Arteries with Implications for the Interventional Radiologist

PURPOSE

To document and assess the genicular arterial variation in a large multicenter cadaveric sample and generate an anatomical classification with implications for Genicular Artery Embolization (GAE).

MATERIALS AND METHODS

A sample of 212 donor body lower limbs were dissected from three medical school institutions. The descending genicular artery (DGA), superior lateral genicular artery, superior medial genicular artery, middle genicular artery, inferior lateral genicular artery, inferior medial genicular artery, and anterior tibial recurrent artery (ATRA) were identified for gross anatomical appearance, location of origin, diameter of vessels, and variation in branching patterns.

RESULTS

A total of 198 DGA, 204 popliteal origin genicular arteries and 183 ATRA were adequately preserved and reviewed. Three types (A:26%, B: 71%, C:5%) of DGA branching patterns were proposed along with six types (I: 28%; II: 22%; III 15%; IV: 15%: V 10%; VI: 6%) of popliteal origin genicular artery branching variants. Right vs left comparisons did not reveal clinically significant differences in vessel distance (p = 0.30 - 0.82).

CONCLUSION

Despite the large number of possible anatomical variations of the genicular arteries, six main patterns corresponded to over 96% of the cases. The description and classification of the genicular arterial anatomy may provide useful information to the interventional radiologist and add to the technical nuances of GAE.

Risk factors for oral epithelial dysplasias to become malignant: clinical implications

There is a lack of effective clinical management of oral epithelial dysplasias to reduce their risk of malignant transformation and considerable gaps in knowledge regarding the most effective means of treating such lesions. A retrospective cohort of biopsy-confirmed oral epithelial dysplasias consecutively diagnosed in the period 1995-2014 and followed-up until 2017 was identified from pathology department files. Demographic, clinical and follow-up information was collected. Multivariate Cox proportional-hazards models were performed to evaluate sociodemographic, clinical and pathological factors associated with progression to oral squamous cell carcinoma. The study included 144 oral epithelial dysplasias, of which 42% progressed to oral cancer at the end of follow-up (21 years). Clinical aspect of the lesion was described for 77 (53.5%) of the patients. Treatment, age, grade of the lesion and diagnostic period were independent prognostic factors for progression. When considering only patients with described clinical aspect, only treatment and grade of the lesion were independently associated with cancer. The results from this non-selected retrospective cohort of oral epithelial dysplasias underscore the existing limitations of the current standard-of-care of the patients and provide novel insights on the management of these lesions with and without described clinical aspect. Well-designed, robust prospective studies, a homogenized staging system and multidisciplinary treatment guidelines are warranted.

Adapting Rapid Diagnostic Tests to Detect Historical Dengue Virus Infections

The only licensed dengue vaccine, Dengvaxia®, increases risk of severe dengue when given to individuals without prior dengue virus (DENV) infection but is protective against future disease in those with prior DENV immunity. The World Health Organization has recommended using rapid diagnostic tests (RDT) to determine history of prior DENV infection and suitability for vaccination. Dengue experts recommend that these assays be highly specific (≥98%) to avoid erroneously vaccinating individuals without prior DENV infection, as well as be sensitive enough (≥95%) to detect individuals with a single prior DENV infection. We evaluated one existing and two newly developed anti-flavivirus RDTs using samples collected >6 months post-infection from individuals in non-endemic and DENV and ZIKV endemic areas. We first evaluated the IgG component of the SD BIOLINE Dengue IgG/IgM RDT, which was developed to assist in confirming acute/recent DENV infections (n=93 samples). When evaluated following the manufacturer's instructions, the SD BIOLINE Dengue RDT had 100% specificity for both non-endemic and endemic samples but low sensitivity for detecting DENV seropositivity (0% non-endemic, 41% endemic). Sensitivity increased (53% non-endemic, 98% endemic) when tests were allowed to run beyond manufacturer recommendations (0.5 up to 3 hours), but specificity decreased in endemic samples (36%). When tests were evaluated using a quantitative reader, optimal specificity could be achieved (≥98%) while still retaining sensitivity at earlier timepoints in non-endemic (44-88%) and endemic samples (31-55%). We next evaluated novel dengue and Zika RDTs developed by Excivion to detect prior DENV or ZIKV infections and reduce cross-flavivirus reactivity (n=207 samples). When evaluated visually, the Excivion Dengue RDT had sensitivity and specificity values of 79%, but when evaluated with a quantitative reader, optimal specificity could be achieved (≥98%) while still maintaining moderate sensitivity (48-75%). The Excivion Zika RDT had high specificity (>98%) and sensitivity (>93%) when evaluated quantitatively, suggesting it may be used alongside dengue RDTs to minimize misclassification due to cross-reactivity. Our findings demonstrate the potential of RDTs to be used for dengue pre-vaccination screening to reduce vaccine-induced priming for severe dengue and show how assay design adaptations as well quantitative evaluation can further improve RDTs for this purpose.

The spectrum of neuropsychiatric lupus in a Black Caribbean population: a report of the Barbados National Lupus Registry

Objective The objective of this study was to examine neuropsychiatric lupus in a Black Caribbean population. Methods We reviewed Barbados National Lupus Registry patients with ≥4 American College of Rheumatology criteria and a diagnosis of neuropsychiatric lupus using the American College of Rheumatology 19 case definitions. Results From 366 patients with four or more American College of Rheumatology criteria for systemic lupus erythematosus, 55 (15%) had evidence of neuropsychiatric lupus. There were 51 females and four males (F:M = 13:1) with a median age of 31 years. A total of 76.4% had a single neuropsychiatric lupus complication and 23.6% had two or three complications occurring sequentially or concurrently. The top three complications were psychosis - 49.1% (95% CI 35.8, 62.5); ischaemic stroke - 32.7% (21.4, 46.5); and generalized tonic-clonic seizures - 12.7% (6.0, 24.8). Twelve of the American College of Rheumatology 19 neuropsychiatric syndromes were represented: 91.2% central; 8.8% peripheral. There were 521 observation years, and for 32 patients (58%) neuropsychiatric lupus was a presenting feature. For the remaining 23 (42%) the first neuropsychiatric lupus event came after systemic lupus erythematosus diagnosis - median time of two years. Of the 22 deaths, systemic lupus erythematosus nephritis caused almost half (45.5%) at a median age of 32. The prevalence of nephritis was lower in the neuropsychiatric lupus subgroup (25.5%) compared with the Barbados National Lupus Registry data (47%) ( P = 0.01). Ischaemic stroke caused 22.7% of deaths at a median age of 46 and was the main cause of chronic neurologic deficits amongst survivors. Conclusion Neuropsychiatric lupus was an early cause of morbidity in systemic lupus erythematosus with predominantly singular central nervous system complications, the most common of which was psychosis. Most deaths occurred at a young age, principally from systemic lupus erythematosus nephritis. Ischaemic stroke was the main neurologic cause of death and disability.

Fabrication of well-ordered silicon nanopillars embedded in a microchannel via metal-assisted chemical etching: a route towards an opto-mechanical biosensor

Nanofabrication methodology that integrates the creation of silicon nanopillars inside a microfluidic channel which has significant implications for the achievement of new optomechanical biosensors.

202 SEX PRE-SELECTION IN RABBITS: AN ATTEMPT TO SKEW OFFSPRING SEX THROUGH PERCOLL AND SWIM-UP SPERM PREPARATION TECHNIQUES

Sperm preparation techniques could have an effect on the birth ratio (male vs female offspring) through enrichment of either X- or Y-bearing sperm populations, although studies have been poorly controlled and results have been inconclusive. In the rabbit, producers may be interested in producing a majority of males (meat producing systems) or females (hybrid producing systems). The objective of this study was to evaluate the effect of modified Percoll and Swim-up protocols on the enrichment of the male and female birth ratios in rabbits. Four hybrid mature bucks of adequate body condition score and proven fertility were used. The same four bucks were used throughout the study (8 replicates). Ejaculates were collected using a warmed, solid, artificial vagina. Progressive motility was assessed at 200× magnification under brightfield microscopy on a heated (37°C) stage. Sperm concentration for each buck was determined using a Neubaur chamber and adjusted (350 × 106 total spermatozoa mL–1); they were then combined (1 mL/buck) to form a heterospermic sample (final heteropsermic sample volume = 4 mL). The heteropsermic sample was then divided into 3 sperm preparation treatments: (1) diluted in commercial tri-buffered extender followed by immediate AI (control); (2) modified Percoll centrifugation in a 90 to 45% density gradient (diluted in human tubal fluid medium); and (3) Swim-up (in human tubal fluid medium). In total, 125 females were inseminated. Does were treated with PMSG (20 UI/doe, 48 h before AI) and inseminated with 30 to 40 × 106 spermatozoa; ovulation was induced with 20 μg of gonadotropin-releasing hormone (GnRH)/doe immediately after AI. Sex of newborn kits was determined 35 days after birth by an experienced technician through external visualization of genitalia. Results were statistically analyzed using ANOVA and Tukey test (Infostat). The insemination of does with heterospermic ejaculates (control) resulted in a progeny distribution of 49 ± 2% males and 51 ± 2% females, which is in good agreement with the expected theoretical 50:50 ratio. Sex ratios from modified Percoll and Swim-up treatments deviated significantly from the control (P < 0.01). Percoll gradient resulted in a progeny distribution of 32 ± 2% males and 68 ± 2% females; Swim-up resulted in a 64 ± 2% male and a 36 ± 2% female distribution (P < 0.01), whereas prolificacy, perinatal mortality and birth weight were not affected by treatment (Table 1). Our results indicate sperm preparation techniques could be used to skew birth ratios towards male or female offspring in rabbits; Percoll preparation could be used to increase proportion of female kits whereas Swim-up could be used to increase the proportion of males. Further studies are needed to determine the underlying mechanisms of action. Table 1.Progeny distribution after Percoll or Swim-up sperm preparation in rabbits

48 EFFECT OF TREHALOSE ADDITION ON IN VITRO VIABILITY OF COOLED RAM SPERMATOZOA

Refrigeration of ovine spermatozoa is a valuable tool for genetic progress. Sugars, in particular disaccharides, have been shown to have positive effects in semen extender, providing energy substrate during cell incubation, decreasing osmotic pressure, causing cell dehydration and ultimately reducing cold shock and cryodamage. Several authors have reported changes in plasma membrane protein organisation and membrane fluidity during cooling. Trehalose, a non-reducing disaccharide has been associated with stabilisation of cellular proteins and interaction with membrane phospholipids due to its ability to replace water at the membrane-solution interface. Many studies have confirmed the beneficial effect of the addition of trehalose during cryopreservation at –196°C; however, its effects during refrigeration (5–7°C) have not been reported. Ejaculates form four fertile Corriedale rams were collected by electroejaculation during the ovine reproductive season in the Southern Hemisphere (May–August); the study was conducted in 12 replicates. After initial quality assessment, ejaculates were pooled into heterospermic samples, diluted in Tris-buffered extender and separated into treatments consisting of (a) no refrigeration (kept at room temperature 22–25°C), (b) refrigeration (cooling rate of 2°C/3 min to reach a final temperature of 5–7°C), or (c) refrigeration with the addition of 150 mOsm trehalose. Samples were evaluated for total motility, progressive motility, hyposmotic swelling test (HOST) and eosin Y (1 step, WHO protocol) live/dead stain at 0, 6, 12, 24 and 48 h post-refrigeration. Results were analysed using 1-way ANOVA with Tukey post-hoc multiple comparison test. Compared with refrigeration without the addition of disaccharides, the refrigeration in presence of trehalose significantly increased (P < 0.05) total motility at 48 h (32 ± 0.9 vs 50 ± 1.1) and progressive motility at 24 (40 ± 0.9 vs 65 ± 0.6) and 48 h (0 vs 38 ± 1.0) post-refrigeration. Trehalose also decreased (P < 0.05) the percentage of damaged spermatozoa as evidenced by HOST and live/dead stain after 12 (42 ± 1.1 vs 29 ± 0.7), 24 (52 ± 0.9 vs 37 ± 0.6) and 48 h (74 ± 0.8 vs 60 ± 1.0) of refrigeration. Although no statistical difference was detected, there was a trend of trehalose to improve total and progressive motility parameters at the initiation of treatments (0 h). In addition, spermatozoa refrigerated in the presence of trehalose was the only treatment group to retain progressive motility after 48 h of storage. Our results indicate that trehalose could be used to extend the in vitro viability of refrigerated ovine spermatozoa for up to 48 h. Further studies are needed to assess the in vivo fertility (pregnancy rate) of refrigerated spermatozoa in the presence of this non-permeating cryoprotectant sugar.

Influence of temperature variations on the average grayscale of B-mode images of HIFU-induced lesions

The aim of this work is to understand how the variations in grayscale values of B-mode ultrasound (US) images can be used as an approach for non-invasive temperature estimation. In order to obtain real-time monitoring of HIFU treatment, an US imaging system and HIFU were synchronized. Images were acquired using an electronic convex imaging probe. An 8% BSA tissue-mimicking polyacrylamide gel was used for the experiments. First, the HIFU power was set to 10 W. The application of HIFU resulted in the appearance of hyperechoic regions that were used to place a thermocouple tip at the focal spot by means of US imaging. Afterwards, the power was gradually increased up to 40 W for 4 min. The temperature sampling rate was set to 5 Hz. For each temperature sample the synchronization system captured one frame. The region of interest (ROI) was manually selected and a set of morphological operations were implemented in order to obtain the shape and size of the thermal lesion. From here, the average grayscale (AGS) and area of the thermal lesion were calculated to assess temperature quantification. The AGS parameter showed a maximum correlation coefficient of 0.6626 as a function of temperature whereas the thermal lesion appeared. In contrast, area values showed a greater correlation coefficient of 0.9122. In conclusion, temperature shows a non-linear behavior with respect to the parameters estimated due to the nature of the thermal lesion formation by HIFU exposure.

The relationship between sources of motivation and level of practice in young Portuguese swimmers

AIM

The aim of this study was to examine the relationship between participation motives and level of practice in young Portuguese swimmers and to investigate whether swimmers with a different expertise differ in their reasons for participation involvement.

METHODS

A total of 155 subjects (68 male and 87 female), aged 7 to 18 years, responded to the Portuguese versions of the Participation Motivation Inventory. The subjects were divided into those participating in learn-to swim programs (n=40), advanced programs (n=49) or competition (n=56).

RESULTS

A significant multivariate effect was obtained for level of practice, with children involved in learn-to swim programs rating fitness, competition, general affiliation, technical skills and fun significantly lower in importance than the other two groups. A 2 (subject gender) x3 (practice level) MANCOVA, with age at dropout, revealed that the effect of the covariate itself was not significant, but a main effect was found for gender, differing boys and girls only in the emotion factor. A significant interaction was also detected between gender and participation level, with a higher importance given to general affiliation by girls in comparison to boys in the advanced programs and competition categories.

CONCLUSION

Our results in a sample of Portuguese swimmers indicate the existence of multiple motives for participation and significant differences in motivational factors in relation to the practice level.

Switching to the bingeing/purging subtype of anorexia nervosa is frequently associated with suicidal attempts

OBJECTIVE

Anorexia nervosa has the highest suicide mortality ratio of psychiatric disorders, suicide being associated with many factors. We assessed the first lifetime occurrence of these factors taking into account their possible overlap.

METHOD

Three hundred and four in- and out-patients with anorexia nervosa (DSM-IV) were systematically recruited in three hospitals of Paris suburbs, between December 1999 and January 2003. Patients were assessed by a face-to-face interview (DIGS). Current eating disorder dimensions were measured, and patients interviewed by a trained clinician to assess minimal BMI and, retrospectively, the age at which anorexia nervosa, major depressive disorder, anxiety disorders and switch to bingeing/purging type occurred for the first time, if applicable.

RESULTS

Major depressive disorder (p<0.001) and subtype switch from the restrictive to the bingeing/purging type (p<0.001) were the two factors significantly more frequently occurring before suicidal attempts, and remained involved when a multivariate analysis is performed, whether syndromic or dimensional measures are being used. Taking into account lifetime occurrence with a survival analysis, the switch to bingeing/purging type of anorexia appears as a major predictive factor, with a large increase of the frequency of suicidal attempts (OR=15) when compared to patients with neither major depressive disorder nor bingeing/purging type.

CONCLUSIONS

Bingeing/purging type of anorexia nervosa is largely associated with suicidal attempts, and may deserve specific attention. If confirmed on a prospectively designed study, these results would argue for early detection and/or more intensive and specific therapeutic intervention on this aspect of bingeing and purging behaviors.

Relationship between perceived physical ability and sport participation motives in young competitive swimmers

AIM

The purpose of this study was to examine the relationship between participation motives and perceived physical ability in young Spanish swimmers and to investigate whether swimmers with high or low perceived physical competence differ in their intrinsic and/or extrinsic reasons for participation involvement.

METHODS

Four hundred and twenty-eight swimmers (204 boys and 224 girls), aged 8-22 years, responded to the Spanish versions of the Participation Motivation Inventory (PMI) and the Perceived Physical Ability Scale (PPA). Swimmers were divided into low (below the 33%), medium (between the 33-66%) and high (above the 66%) perceived ability groups.

RESULTS

Multivariate analysis indicated the existence of differences in motives for participation between swimmers with different levels of perceived physical ability. Follow-up univariate analyses yielded significant (p<0.05) effects for 5 motivational factors: health/fitness, fun/friendship, competition/skills, affiliation and status. In all cases swimmers high in perceived physical ability rated significantly higher than those in the other categories. The PPA by gender, age or level of expertise interaction was not significant.

CONCLUSIONS

Practitioners must consider the perceived ability of the competitors to better structure the social environment within which their swimmers operate.

Validity and reliability of the Yale Physical Activity Survey in Spanish elderly

BACKGROUND

The purpose of this study was to validate a Spanish version of the Yale Physical Activity Survey (YPAS) in a population of older adults and to estimate its potential for application in routine physical activity assessment in the elderly.

METHODS

A group of 108 (38 men and 70 women) community dwelling, healthy people aged 61-80 yrs responded twice the questionnaire with an interval of two weeks.

RESULTS

Test-retest correlations were significant for the total time and energy expenditure. A moderate but also significant agreement was found for the different summary indices. Significant correlations were found for all of the checklist activities and mean differences between the first and second administration did not reach statistical significance for any scores. Total time and energy expenditure correlated positively with Caltrac activity units and negatively with body weight. The activity dimension summary index and the individual index of leisure walk were significantly associated with Caltrac units and negatively with the percentage of body fat. The summary index and the individual index of vigorous activity correlated significantly with the body mass index and the moving index with Caltrac units. A positive association was found between body mass and sitting index.

CONCLUSIONS

The Spanish version of the YPAS probed to be a reasonable valid and reliable measure of physical activity in older adults.

Comparative hydrodynamic evaluation of bioprosthetic heart valves

BACKGROUND AND AIM OF STUDY

Pressure gradients across cardiac valve prostheses have been identified as one of the most important performance measures in valve replacement surgery. Specifically in aortic valves, these gradients influence reduction of left ventricular hypertrophy and are postulated to influence long-term survival. The correct choice of replacement valve is hampered by a lack of uniform measures of valve performance. The aim of this study was to compare in-vitro hydrodynamic performance of commercially available bioprosthetic valves under identical test conditions.

METHODS

In-vitro steady forward flow and pulsatile flow tests were performed on aortic and mitral bioprosthetic valves in accordance with ISO/FDA guidelines at two different institutions to obtain objective hemodynamic performance measures. Measurements were recorded at various flow rates, flow and pressure to obtain mean pressure gradients and effective orifice areas (EOAs).

RESULTS

Wide variation in pressure gradients was found among tested valves of each size. For a given size, differences of 200 to 400% were observed; in general, the valve models' relative rankings in pressure drop were independent of size.

CONCLUSION

The Carpentier-Edwards Perimount valve showed superior performance at all sizes tested. While the mean pressure gradients and EOAs reported by each institution differed for a given valve, the performance of valve models relative to each other was similar. The testing of valves under identical conditions is a valuable comparative indicator of valve hemodynamic performance.

Relationship of measures of leisure time physical activity to physical fitness indicators in Spanish adults

BACKGROUND

The purpose of our study was to examine the association between estimates of energy expenditure obtained by the Minnesota Leisure Time Physical Activity questionnarie (LTPA) and physical fitness indicators. METHODS.

PARTICIPANTS

An adaptation of the LTPA was assessed in a sample of Spanish population: male (n = 44) and female (n = 38).

INTERVENTIONS

the LTPA 1 year recall questionnaire was administered twice with a 12-month interval and participants also responded monthly the Four Week Physical Activity History (FWH) questionnaire.

MEASURES

test-retest reliability of the LTPA and the relationships between changes in V.O2max, percent body fat and leisure time physical activity were examined.

RESULTS

Corresponding components of the LTPA and the FHW were highly correlated and scores in heavy leisure time activities and household chores showed a relatively low variance ratio, indicating an acceptable reliability of the questionnaire. Heavy intensity physical activity and household chores were highly related to V.O2max and there was a weaker association to moderate or light activity.

CONCLUSIONS

Our results suggest that the Spanish version of the LTPA is a relatively valid and reliable measure of regular physical activity and a valid estimator of cardiorespiratory fitness in adults.

Stereotactic radiosurgical boost following radiotherapy in primary nasopharyngeal carcinoma: impact on local control

PURPOSE

Treatment of patients with nasopharyngeal carcinoma using external beam radiation therapy (EBRT) alone results in significant local recurrence. Although intracavitary brachytherapy can be used as a component of management, it may be inadequate if there is extension of disease to the skull base. To improve local control, stereotactic radiosurgery was used to boost the primary tumor site following fractionated radiotherapy in patients with nasopharyngeal carcinoma.

METHODS AND MATERIALS

Twenty-three consecutive patients were treated with radiosurgery following radiotherapy for nasopharyngeal carcinoma from 10/92 to 5/98. All patients had biopsy confirmation of disease prior to radiation therapy; Stage III disease (1 patient), Stage IV disease (22 patients). Fifteen patients received cisplatinum-based chemotherapy in addition to radiotherapy. Radiosurgery was delivered using a frame-based LINAC as a boost (range 7 to 15 Gy, median 12 Gy) following fractionated radiation therapy (range 64.8 to 70 Gy, median 66 Gy).

RESULTS

All 23 patients (100%) receiving radiosurgery as a boost following fractionated radiation therapy are locally controlled at a mean follow-up of 21 months (range 2 to 64 months). There have been no complications of treatment caused by radiosurgery. However, eight patients (35%) have subsequently developed regional or distant metastases.

CONCLUSIONS

Stereotactic radiosurgical boost following fractionated EBRT provides excellent local control in advanced stage nasopharynx cancer and should be considered for all patients with this disease. The treatment is safe and effective and may be combined with cisplatinum-based chemotherapy.

Use of the peritracheal fold in the dog tracheal transplantation model

OBJECTIVE

To investigate the technical aspects of the canine model of human tracheal transplantation for potential application to reconstruction of extremely long tracheal defects (> 10 cm).

DESIGN

In phase 1, long tracheal segments were skeletonized and pedicled with the thyroid glands, cranial thyroid arteries and veins, and internal jugular vein branches. The segments were elevated completely, attached to the vascular pedicle only, and replaced with primary tracheal anastomoses. In phase 2, long segments were elevated along with a diffuse soft tissue "blanket" that envelops the trachea and thyroid glands. Because this study was designed to primarily address, in situ, tracheal perfusion territories of a cranially located vascular pedicle, microvascular anastomoses were not conducted.

SUBJECTS

Two small-bodied beagles (10-15 kg) and 5 large-bodied mixed-breed dogs (20-30 kg) were humanely killed 2 to 41 days after surgery, and anatomic and histological analyses were conducted.

RESULTS

Unlike that of humans, the thyroid gland complex of dogs is not intimately associated with the trachea but is conjoined with a peritracheal soft tissue "fold." Within this fold, blood is transmitted to the trachea via a diffuse, segmental vascular plexus. In phase 1, pronounced tracheal necrosis occurred within 2 to 5 days. In phase 2, extremely long tracheal segments (10-12 cm), based only on a cranially located pedicle, were still viable at 2 to 6 weeks.

CONCLUSIONS

Preservation of the "peritracheal fold" in the dog model of tracheal transplantation is critical to the onset and maintenance of vascular perfusion in a long tracheal segment. Furthermore, the use of large-bodied dogs is necessary to provide for a usable venous efflux component.

Maxillary sinus mucosal blood flow during nasal vs tracheal respiration

OBJECTIVE

To determine the effect of changes from nasal to tracheal respiration on maxillary sinus mucosal blood flow in rabbits with unobstructed sinus ostia.

DESIGN

Animals underwent tracheotomy with a T tube and then a small window of intact maxillary sinus mucosa was exposed. Mucosal blood flow was recorded during normal nasal respiration using laser-Doppler velocimetry. At hourly intervals, respiration was changed from the nasal to the tracheal route and then back again.

SUBJECTS

Ten anesthetized rabbits were used: 5 underwent single and 4 underwent multiple shifts in the respiratory route, while 1 was monitored continuously during long-term nasal breathing only.

RESULTS

A significant decrease in maxillary sinus blood flow occurred on switching from nasal to tracheal respiration and a significant increase in blood flow occurred on return to nasal respiration. Where multiple switches were made, blood flow changes diminished in magnitude, but significant decreases (nasal to tracheal) or increases (tracheal to nasal) were evident in all cases.

CONCLUSIONS

It is proposed that the maxillary sinus may act in an accessory capacity to the nose for humidification of inspired air via secretions liberated from the sinus ostium. Furthermore, we suggest that nasal airflow is involved with the reflex regulation of sinus blood flow, probably via stimulation of sensory receptors in the nasal cavity. Reduced maxillary sinus mucosal blood flow may thus contribute to supra-systemic levels of antral carbon dioxide. Since elevated carbon dioxide levels have been shown to reduce maxillary sinus mucociliary activity in vitro, nasal airflow compromise may contribute to the initiation of a cascade of pathophysiological events leading to acute sinusitis.

The expression of an aquaporin promoter from Mesembryanthemum crystallinum in tobacco

The promoter region of the MipB gene encoding an aquaporin from Mesembryanthemum crystallinum was isolated and used in a transcriptional fusion to control uidA expression in tobacco. The sequence of the promoter was determined for 2 kb upstream of the translation initiation site. Three start sites were utilized with approximately equal frequency, located 176, 170, and 161 bases, respectively, upstream of the translation initiation site. As judged by analysis of GUS expression, promoter MipB retains its specificity in transgenic tobacco. In germinating seedlings, all cells showed GUS expression of different intensities with the strongest signals in root meristems. In older seedlings, GUS staining was observed in rapidly expanding cells--root and apical meristem, and lateral root primordia. In mature plants, strong GUS activity was located to glandular trichomes, subepidermal cells of the stem and petioles, to cells surrounding vascular tissues as well as in xylem parenchyma cells. In immature floral organs, GUS expression was strong in sepals, petals, stamen, and pistil. The intensity declined as they matured. In general, this promoter was active in rapidly expanding cells and cells with high water flux capacity, especially in the xylem parenchyma.

Neuropathy in burn patients

Neuropathic complications of the burn patient are frequently undiagnosed. A retrospective study was performed looking at neuropathies in patients admitted to a tertiary care burns centre from 1984 to 1991. Nineteen out of a total of 800 patients had signs and symptoms of neuropathy, confirmed on neurophysiological testing. Most patients were severely burned with 11 patients (69%) having a total burn surface area of > 20%. Twenty-eight percent were full thickness burns. Mononeuritis multiplex was the most common finding in these patients, occurring in 11 (69%). This has not been reported before. Three patients (19%) had an isolated mononeuropathy, one (6%) had a radiculopathy and one had a generalized axonal polyneuropathy. Of the patients with mononeuropathy, nine had lesions only in burned areas and four had lesions in burned and unburned areas. Eleven patients had complications of sepsis with five also having renal failure. Age, sex, serum albumin, magnesium, phosphate, creatinine, the presence of sepsis and the number or type of drug did not correlate with the number of affected nerves nor the extent of recovery. The length of hospitalization and severity of the burns were the only two factors which correlated with the number of affected nerves. Vascular occlusion of the vasa nervorum, direct thermal injury or a disseminated neurotoxin are postulated as possible aetiological mechanisms.

Pott's puffy tumour and subdural empyema following frontal sinusitis

A previously healthy 17-year-old lad presented with purulent sinusitis and subsequently developed subdural empyema in association with Pott's puffy tumour. Complete resolution occurred with an intensive antibiotic regime and drainage of the subgaleal space.

Urban clusters of sexually transmitted diseases in the city of Seville, Spain

To test the hypothesis that there is an increased risk for sexually transmitted diseases in certain geographic areas, 613 patients diagnosed as having sexually transmitted diseases in Seville, Spain, were studied in relation to their address. Increased risks of gonorrhea (relative risk, 3.72), syphilis (relative risk, 3.32), Chlamydia trachomatis infections (relative risk, 3.41), and the three conditions together (relative risk, 3.52) were found in district 1, which represents the core of transmission and the central area of old Seville. These findings represent the first description of spatial clusters for syphilis and Chlamydia trachomatis infections.