On-site quantification of re-entry ratio of ventilation exhausts in multi-family residential buildings and implications.

UNLABELLED: In the worldwide spread of Severe Acute Respiratory Syndrome (SARS) in 2003, cluster of cases occurred in a number of large high-rise residential building blocks, especially in Hong Kong. In this study, we examined one of the most likely virus-spread mechanisms, which is related to the inter-flat or inter-zonal airflow through open-windows caused by buoyancy effects. Dual tracer gases of CO2 and SF6 are employed simultaneously to quantify the amount of the exhaust air coming out of the upper part of the window of a floor that re-enters the lower part of the open-window at the immediate upper floor. It was found that the room air could contain up to 7% of the exhaust air from the lower floor, and this occurs at low wind conditions with a combination of indoor-outdoor temperature difference. The results can well explain the earlier governmental finding that DNA strings of SARS Corono-Virus were detected within the sampled deposits on the window sills of the upper floors of the two index patients' flats. The preliminary and yet alarming conclusion may be that, in high-rise buildings, windows flush with a flat façade can be a major route for the vertical spread of pathogen-containing aerosols. PRACTICAL IMPLICATIONS: The confirmation of the transmission route can have a number of implications to both building design and infectious disease control. With respect to the former, considerations should be given to minimize the inter-flat airflow via windows flush with façade for high-rise buildings with natural ventilation; and with respect to the latter, more targeted and earlier intervention can be implemented in case of any highly infectious disease outbreaks.

Endoscopic shaver with liposuction for treatment of axillary osmidrosis.

Axillary osmidrosis is a distressing problem, and in severe cases patients may seek a permanent solution. Many treatment techniques have been developed that involve destruction or removal of the apocrine and eccrine glands. Previous methods have been hampered by surgical or aesthetic concerns. From June 1999 to June 2000, 64 patients (43 women and 21 men) were treated surgically for axillary osmidrosis. A 1-cm incision is made in the axillary crease. An endoscopic shaver is inserted, extended to the edge of the axilla, and subcutaneous tissue and glands are excised as the shaver is drawn from the axillary edge to the crease. Suction connected to the shaver immediately removes excised tissue. This procedure is repeated throughout the entire axilla. Malodor elimination was good in 117 of 128 axillae (91.4%) treated, fair in 8 (6.3%), and poor in 3 (2.3%). The resulting scar is small and essentially invisible because it is located in the axillary crease. This technique results in a small, inconspicuous scar; a surgical time of only 40 minutes; patients resuming exercise and daily activities within 5 days of surgery; and high patient satisfaction.

Psychometric properties of the Portuguese version of the State-Trait Anxiety Inventory applied to college students: factor analysis and relation to the Beck Depression Inventory.

The psychometric properties of the Portuguese version of the trait form of the State-Trait Anxiety Inventory (STAI-T) and its relation to the Beck Depression Inventory (BDI) were evaluated in a large Brazilian college student sample containing 845 women and 235 men. STAI-T scores tended to be higher for women, singles, those who work, and subjects under 30 years. Factor analysis of the STAI-T for total sample and by gender yielded two factors: the first representing a mood dimension and the second being related to worrying or cognitive aspects of anxiety. In order to study the relation between anxiety and depression measures, factor analysis of the combination of the 21 BDI items and the 20 STAI-T items was also carried out. The analysis resulted in two factors that were analyzed according to the tripartite model of anxiety and depression. Most of the BDI items (measuring positive affectivity and nonspecific symptoms of depression) were loaded on the first factor and four STAI-T items that measure positive affectivity. The remaining STAI-T items, all of them measuring negative affect, remained in the second factor. Thus, factor 1 represents a depression dimension and factor 2 measures a mood-worrying dimension. The findings of this study suggest that, although widely used as an anxiety scale, the STAI-T in fact measures mainly a general negative affect.

Psychometric properties of the Portuguese version of the State-Trait Anxiety Inventory applied to college students: factor analysis and relation to the Beck Depression Inventory

The psychometric properties of the Portuguese version of the trait form of the State-Trait Anxiety Inventory (STAI-T) and its relation to the Beck Depression Inventory (BDI) were evaluated in a large Brazilian college student sample containing 845 women and 235 men. STAI-T scores tended to be higher for women, singles, those who work, and subjects under 30 years. Factor analysis of the STAI-T for total sample and by gender yielded two factors: the first representing a mood dimension and the second being related to worrying or cognitive aspects of anxiety. In order to study the relation between anxiety and depression measures, factor analysis of the combination of the 21 BDI items and the 20 STAI-T items was also carried out. The analysis resulted in two factors that were analyzed according to the tripartite model of anxiety and depression. Most of the BDI items (measuring positive affectivity and nonspecific symptoms of depression) were loaded on the first factor and four STAI-T items that measure positive affectivity. The remaining STAI-T items, all of them measuring negative affect, remained in the second factor. Thus, factor 1 represents a depression dimension and factor 2 measures a mood-worrying dimension. The findings of this study suggest that, although widely used as an anxiety scale, the STAI-T in fact measures mainly a general negative affect

Life-threatening bleeding in a facial fracture.

Life-threatening bleeding in facial fractures is considered rare, and most reports do not recommend a precise treatment guideline. Although various methods have been suggested, they are unpredictable in efficacy and may lead to irreversible shock. To avoid irreversible shock, early detection and correct, effective treatment are mandatory. The authors report a patient who presented with a complex midface fracture after falling on June 23, 1999. Life-threatening oronasal bleeding developed 1 hour after arriving at the emergency room. Initial nasal packing failed to stop the nasal bleeding. After resuscitation, the patient's vital signs were stable but bleeding persisted. Angiography showed diffuse extravasation of contrast medium over the territory of the right internal maxillary artery. Embolization was performed successfully to stop the bleeding. The authors review the literature regarding the incidence, diagnosis, and treatment of life-threatening facial fracture. In the literature, the lack of a precise definition leads to various results by various treatments. The authors have formulated a succinct treatment guideline. They favor angiographic embolization as the first choice of treatment when tight nasal and/or oral packing fails.

Acute life-threatening injuries in facial fracture patients: a review of 1,025 patients.

BACKGROUND: The literature on facial fractures has emphasized obstruction of the airway as the most common associated life-threatening problem. Other life-threatening injuries associated with facial fractures are not as well documented. For this reason, we conducted a retrospective study involving 1,025 patients with facial fractures admitted to the trauma center at Chang Gung Memorial Hospital in Taiwan from January 1995 through December 1998. METHODS: This study identifies the incidence of facial fractures and establishes a management plan. Life-threatening injuries associated with facial fractures were those that warranted immediate invasive rescue procedures. RESULTS: Sixty-four (6.2%) of the patients with facial fractures required life-saving intervention; 21 patients had cerebral trauma prompting craniotomy, 19 had hemorrhagic shock, 17 had airway compromise, and 7 had pulmonary injury grave enough to necessitate tube thoracostomy. There were five mortalities, three due to cerebral trauma and two credited to hemorrhagic shock not identified until long after admission. CONCLUSION: These findings illustrate the need for prompt identification and proper management of the associated life-threatening injuries in facial fracture patients. Clinical assessment should begin with evaluation of cerebral trauma, followed by hemorrhagic shock, airway compromise, and hemopneumothorax. Proper management may require a multidisciplinary and coordinated team approach.

Application of endoscope in zygomatic fracture repair.

The endoscope has been used to visualise the upper face and brow in aesthetic facial surgery which is performed without a coronal incision. We applied these principles to repair zygomatic fractures with the aid of a 4 mm, 30 degree telescope inserted through a small temporal incision. Fracture sites at the zygomatic arch and the zygomaticofrontal suture were exposed and fixed with miniplates under endoscopic control. This technique was used in 15 consecutive patients including 2 with isolated zygomatic arch comminuted fractures and 13 having displaced zygomatic fractures with segmental, displaced zygomatic arch fractures. Nine patients were men and six patients were women with a mean age of 35 years. Three patients had associated mandibular fractures. The periods of follow-up ranged from 3 to 22 months. Two patients developed transient frontal nerve palsy which recovered within 2 months. One patient had mild temporal hollowing on the side of the facial fracture. All patients achieved the adequate anatomic reduction and satisfactory malar symmetry. There has been no case of chewing problems, cheek numbness or progressive enophthalmos developing postoperatively. Application of the endoscope in zygomatic fracture repair minimises the scalp scar, avoids forehead numbness, provides a comfortable postoperative recovery and shortens hospital stay. Careful preoperative evaluation and proper surgical technique are mandatory for achieving optimal results in selected patients.

Microsurgical combined scapular/parascapular flap for reconstruction of severe neck contracture: case report and literature review.

OBJECTIVE: The reconstruction for severe neck contracture is difficult, because it may include not only the necessity the use of a large flap but also the ability for three-dimensional movement of the neck. METHODS: A 41-year-old woman sustained a severe neck contracture with retraction of the lower lip and limited range of neck motion after a chemical burn. We used the combined scapular/parascapular flap to reconstruct the soft-tissue defect in the neck after excision of hypertrophic scar and release of contracture. The scapular portion was transferred to cover the defect vertically, and the parascapular portion was transferred to cover the transverse portion of the neck. This kind of design would allow the patient to move her neck more easily. RESULTS: Postoperatively, the range of motion of the neck was full in the vertical and horizontal directions after 6 months of rehabilitation. Also, the patient was satisfied with the final aesthetic results. CONCLUSION: The microsurgical combined scapular/parascapular flap, providing a large area of tissue for coverage in three dimensions with a reliable blood supply by only one pedicle anastomosis during surgery, is a good option for reconstruction of the severe neck contracture. We classify the inset of the combined scapular/parascapular flap into three types with six subtypes, according to the location of defects and the relation of the parascapular flap to the scapular flap.

Psychometric properties of the Portuguese version of the Beck Depression Inventory on Brazilian college students.

The psychometric properties of the Portuguese version of the Beck Depression Inventory were studied on a large Brazilian college student sample (N= 1,080; 845 women, 235 men). The BDI scores according to sociodemographic characteristics and mean individual item scores for total sample and by gender were compared. BDI scores tend to be higher for women, for those who work, and for the younger participants. The reliability of the inventory estimated by alpha coefficient was high for the total sample (.86) and subgroups. Factor analysis showed three factors for the total sample (low self-esteem, cognitive-affective, and somatic) and two for each gender. Women combined affective and low self-esteem whereas men combined somatic and low self-esteem in the same dimension. Discriminant analysis showed that BDI highly discriminates depressive symptomatology in college students and measures specific aspects of depression.

Radon emanation of building material--impact of back diffusion and difference between one-dimensional and three-dimensional tests.

Small-scale chamber experiments were conducted to investigate the radon emanation rates of commonly used building materials such as bare concrete, granite, red brick, and sand brick. It has been found that back diffusion caused by the accumulation of radon in the indoor environment has significant influence on the radon emanation rate. The radon emanation rate can be expressed as the summation of an initial emanation rate and the product of a specific back diffusion coefficient and the indoor radon level. In some occasions the radon emanation rate can be significantly lower than its initial value. A database was developed summarizing results from 26 samples. The influence of relative humidity on the radon emanation characteristics has also been discussed. Separate tests were done by coating the four sides of the building material with silicone gel to simulate a one-dimensional radon diffusion geometry. The results show that a factor has to be included when the three-dimensional test results are used to describe one-dimensional geometry, such as radon emanation from building wall surfaces.

Endoscopically assisted reconstruction of orbital medial wall fractures.

Traditional surgical approaches to orbital medial wall fractures are either direct extraocular skin incisions or indirect bicoronal flap. However, these methods can leave remarkable orbital scars or scalp alopecia with the possible associated complications. A minimally invasive endoscopic technique with the assistance of a 2.7-mm, 30-degree telescope through a medial transconjunctival incision has been successfully used to reconstruct the orbital medial wall fractures. This technique was applied to four patients who had orbital medial wall fractures. Three patients also had concomitant orbital floor fractures. The other had associated superior orbital fissure syndrome. All patients were presented with limited eye movement, positive forced duction test, horizontal diplopia, and enophthalmos (3 mm to 6 mm) preoperatively. The entrapped periorbital tissues in the ethmoid sinus were completely reduced endoscopically. The bone defect of orbital medial wall was reconstructed with autogenous rib bone grafts under endoscopic control. The patients were followed up for 8 to 16 months with an average of 11 months. Three patients recovered completely without any residual eye symptoms after intervention. Clinically significant residual enophthalmos of 3 mm occurred in the patient with the superior orbital fissure syndrome. His eye movement limitation caused by entrapment of medial rectus muscle was relieved postoperatively. There was no donor-site morbidity or any complications related to the endoscopically assisted procedure. Endoscopically assisted medial transconjunctival approach to the orbital medial wall fractures is an excellent adjunct for the exposure and complete reduction of herniated periorbital tissue and bony reconstruction of the medial orbital wall.

Endoscopically assisted mandibular subcondylar fracture repair.

The endoscope has been widely used in aesthetic surgery in recent years, but rarely has it been used in cases of facial trauma. From July of 1996 to December of 1996, the endoscope was used successfully to assist in the repair of mandibular subcondylar fractures in eight patients (five men and three women). Their ages ranged from 15 to 60 years with an average age of 31 years. Six of the patients had other associated mandibular fractures including angular, parasymphyseal, and contralateral subcondylar fractures. A 4.0-mm, 30-degree telescope was introduced to visualize the fracture site by means of an intraoral incision over the ascending ramus. A miniplate was used to stabilize the fracture site with the help of a percutaneous trocar. Intermaxillary fixation was applied for 3 to 6 days. Functionally, all patients returned to normal range of motion within 8 weeks. A slight deviation to the trauma site was noted on maximal opening in three patients, but this condition returned to normal 3 months after surgery. There was no facial palsy or lip numbness. The benefits of the endoscopic approach include not only the provision of better visualization and precise anatomic alignment of bony segments but also the avoidance of large facial scars and facial nerve injuries.

A comparative study of various fixation methods for mandibular fracture.

BACKGROUND: Internal rigid fixation for mandibular fractures has been recognized as a reliable method for obtaining osteosynthesis. It may allow for early active physiotherapy and resumption of normal function. However, few studies have compared the various fixation methods. METHODS: From January 1993 through December 1997, 101 patients with mandibular fractures, who were selected for study, received treatment using various fixation methods at the Craniofacial Center, Chang Gung Memorial Hospital. The fixation methods included plate fixation in 44 patients, lag screw fixation in 30, combined plate and lag screw fixation in 15, and wire fixation in 12. Clinical data assessment was performed by reviewing hospital records. For assessment of the long-term surgical results, the patients were asked to complete a questionnaire including questions which specifically targeted history regarding occlusion, mastication, facial asymmetry, width of mouth opening, and general appearance. RESULTS: The outcome assessment showed statistically different results among the groups. The wire group required intermaxillary fixation more often and for a longer duration compared to the groups using plates and/or lag screws. The plate, lag screw, and combined plate and lag screw fixation groups had better total outcome scores, in particular for long-term dental occlusion and mastication function. CONCLUSION: This study shows that for mandible fractures, the more rigid types of fixation methods, i.e., plates and screws or lag screws, can offer better short and long-term outcomes.

Successful replantation of an avulsed middle finger.

In avulsion amputations of the digits, soft-tissue injuries are extensive and often require tendon, nerve, and vessel transfers or grafts. The functional results of such digital replantations are frequently less than ideal. Therefore, avulsion amputation of a single digit proximal to the insertion of the flexor digitorum superficialis has been a contraindication to replantation, because the anticipated poor functional result may interfere with overall hand function, and is not worth the sacrifice of a tendon, nerve, or vessel from another digit or transfer. The authors report a patient with avulsion amputation of the middle finger at the proximal interphalangeal joint. The digit was replanted successfully without any tissue transfers other than a radial digital artery from the ring finger. The functional results were good, and the authors believe that good functional and cosmetic results can be achieved in select patients with isolated digital avulsions, provided that an experienced hand microsurgeon and a skillful hand therapist are available for a compliant patient.

Silicone molar block used as a fulcrum in condylar surgery.

The narrowness of the temporomandibular joint (TMJ) can cause difficulty in open reduction and fixation of condylar fracture. The authors designed a silicone block that acts as a fulcrum to create more space around the TMJ. The block is made of high-quality silicone that is firm, elastic, nontoxic, autoclave tolerant, and harmless to dental tissue. This block has been used successfully in facilitating reduction and fixation of condylar fractures in 27 patients, and for releasing spastic muscles during closed reduction in 2 patients with prolonged TMJ dislocation. In edentulous patients, the silicone molar block can be used as a mouth opener to facilitate most intraoral procedures without injury to the gum.

Preformed IgG antibodies against major histocompatibility complex class II antigens are major risk factors for high-grade cellular rejection in recipients of heart transplantation.

BACKGROUND: Preformed anti-HLA antibodies reacting specifically with donor lymphocytes have been associated with acute vascular rejection and early cardiac allograft failure. However, the effect of preformed anti-HLA antibodies directed against allogeneic major histocompatibility complex (MHC) class I or II antigens of a donor panel on heart transplantation outcome has not been extensively studied. METHODS AND RESULTS: The study group consisted of 68 patients who received cardiac transplants between 1989 and 1996 and who were at high risk for developing anti-HLA antibodies before transplantation. The effect of preformed antibodies against allogeneic MHC class I or class II antigens on the development of early high-grade cellular rejection and on cumulative annual rejection frequency was determined. Both patients with left ventricular assist devices and retransplantation candidates had a similar increase in the frequency of IgG anti-MHC class II antibodies (IgG anti-II) compared with control subjects (P<0.0001), whereas the frequency of IgG anti-MHC class I antibodies (IgG anti-I) was elevated only in patients with left ventricular assist devices. Pretransplantation IgG anti-II predicted early development of high-grade cellular rejection (P=0.006) and higher cumulative annual rejection frequency (P<0.001) in both of these sensitized patient groups. Among retransplantation recipients, a match between donors 1 and 2 at HLA-A additionally predicted an earlier time to a high-grade cellular rejection. CONCLUSIONS: These results emphasize the importance of specifically screening heart transplantation candidates for the presence of IgG antibodies directed against MHC class II molecules and suggest that strategies aimed at their reduction may have an impact on the onset and frequency of high-grade cellular rejections after transplantation.

An immunological algorithm to predict risk of high-grade rejection in cardiac transplant recipients.

BACKGROUND: Transplant-related coronary-artery disease (TCAD) develops frequently in cardiac-allograft recipients, and limits long-term survival. We examined the relation between this disorder and cumulative frequency of high-grade rejection, and investigated whether concomitant use of three immunological factors at the time of a low-grade endomyocardial biopsy can predict progression to high-grade rejection. METHODS: We investigated the relation between the cumulative annual frequency of high-grade rejection and TCAD in 198 recipients of cardiac transplantation between 1992 and 1996 by means of Kaplan-Meier actuarial life-tables. Endomyocardial biopsy, lymphocyte-growth assays, and anti-HLA antibody measurements were compiled over 12 months in 102 patients during their first post-transplant year. We calculated predictive values for high-grade rejection within 90 days by chi2, Kaplan Meier survival curves, and by multivariable logistic regression analyses. FINDINGS: We found a direct correlation between cumulative annual frequency of rejection and TCAD onset with highest risk in those with more than 0.75 rejections per year (p=0.0002). After a low-grade endomyocardial biopsy (0 or 1A), one or more donor-recipient HLA-DR matches protected against high-grade rejections (p<0.001). Among individuals with one or two DR matches, the negative predictive value for progression from a low-grade biopsy to a high-grade rejection was 87% in the presence of a negative lymphocyte-growth assay. Among individuals with no DR matches, the presence of either a positive lymphocyte-growth assay or IgG anti-major-histocompatibility complex (MHC) class II antibodies was independently associated with high probability of progression to rejection (64% and 66%, respectively, p<0.0005). When both assays were positive, concomitantly with a low-grade endomyocardial biopsy, the positive predictive value for progression to a high-grade rejection was 86% (p<0.0001). For endomyocardial-biopsy grades 1B or 2, a positive lymphocyte-growth assay alone was associated with high-grade rejection in 100% of cases. INTERPRETATION: Use of an algorithm combining three immunological factors at the time of a low-grade endomyocardial biopsy enables prospective stratification of cardiac transplant recipients into risk categories for progression to high-grade rejection. Low-risk individuals require fewer biopsies, moderate-risk individuals require an ongoing schedule of surveillance biopsies, and high-risk individuals require rational organisation of interventional strategies aimed at preventing rejection. Additional predictive factors are needed to identify moderate-risk individuals who will progress to rejection. Ultimately, successful intervention may have an impact on the subsequent complication of TCAD.