COVID-19 and The Promise of Small Molecule Therapeutics: Are There Lessons to be Learnt?

The coronavirus disease 2019 (COVID-19) pandemic had grounded the world to a standstill. As the disease continues to rage two years on, it is apparent that effective therapeutics are critical for a successful endemic living with COVID-19. A dearth in suitable antivirals has prompted researchers and healthcare professionals to investigate existing and developmental drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although some of these drugs initially appeared to be promising for the treatment of COVID-19, they were ultimately found to be ineffective. In this review, we provide a retrospective analysis on the merits and limitations of some of these drugs that were tested against SARS-CoV-2 as well as those used for adjuvant therapy. While many of these drugs are no longer part of our arsenal for the treatment of COVID-19, important lessons can be learnt. The recent inclusion of molnupiravir and Paxlovid™ as treatment options for COVID-19 represent our best hope to date for endemic living with COVID-19. Our viewpoints on these two drugs and their prospects as current and future antiviral agents will also be provided.

Effects of treatment processes on AOC removal and changes of bacterial diversity in a water treatment plant

The effectiveness of different treatment processes on assimilable organic carbon (AOC) removal and bacterial diversity variations was evaluated in a water treatment plant. The van der Kooij technique was applied for AOC analysis and responses of bacterial communities were characterized by the metagenomics assay. Results show that the AOC concentrations were about 93, 148, 43, 51, 37, and 38 μg acetate-C/L in effluents of raw water basin, preozonation, rapid sand filtration (RSF), ozonation, biofiltration [biological activated carbon (BAC) filtration], and chlorination (clear water), respectively. Increased AOC concentrations were observed after preozonation, ozonation, and chlorination units due to the production of biodegradable organic matters after the oxidation processes. Results indicate that the oxidation processes were the main causes of AOC formation, which resulted in significant increases in AOC concentrations (18-59% increment). The AOC removal efficiencies were 47, 28, and 60% in the RSF, biofiltration, and the whole system, respectively. RSF and biofiltration were responsible for the AOC treatment and both processes played key roles in AOC removal. Thus, both RSF and biofiltration processes would contribute to AOC treatment after oxidation. Sediments from the raw water basin and filter samples from RSF and BAC units were collected and analyzed for bacterial communities. Results from scanning electron microscope analysis indicate that bacterial colonization was observed in filter materials. This indicates that the surfaces of the filter materials were beneficial to bacterial growth and AOC removal via the adsorption and biodegradation mechanisms. Next generation sequencing analyses demonstrate that water treatment processes resulted in the changes of bacterial diversity and community profiles in filters of RSF and BAC. According to the findings of bacterial composition and interactions, the dominant bacterial phyla were Proteobacteria (41% in RSF and 56% in BAC) followed by Planctomycetes and Acidobacteria in RSF and BAC systems, which might affect the AOC biodegradation efficiency. Results would be useful in developing AOC treatment and management processes in water treatment plants.

In vitro cytotoxicity testing of a nanocrystalline silver dressing (Acticoat) on cultured keratinocytes

Acticoat is a polyethylene mesh coated with nanocrystalline silver. It has been used widely as a dressing for chronic wounds, acute partial-thickness burn wounds and donor sites. In this study, the in vitro cytotoxicity of Acticoat on cultured keratinocytes is tested. Human keratinocytes are cultivated on a pliable hyaluronate-derived membrane (Laserskin) using dermal fibroblasts as the feeder layer. When the cultured Laserskin (CLS) is subconfluent it is covered by Acticoat, which is exposed to water (Group 1), phosphate-buffered saline (Group 2) or culture medium (Group 3). The control group is not exposed to the Acticoat. After 30 minutes incubation at 37 degrees C, the inhibitory effect of the nanocrystalline silver on keratinocyte growth is measured by an MTT assay. Compared with the control, the relative viability of the CLS dropped to 0%, 0% and 9.3%, respectively. Thus, Acticoat is cytotoxic to cultured keratinocytes and should not be applied as a topical dressing on cultured skin grafts.

Berberine induces apoptosis via the mitochondrial pathway in liver cancer cells

Current chemotherapeutic strategies for liver cancer have limitations. Thus, the demand for complementary medicine is warranted. We evaluated the antitumor potential of berberine, a naturally bioactive phytochemical from Coptis chinensis Franch against Huh7 cancer cells and WRL68 liver cells. The antitumor activity of berberine was evaluated by flow cytometry. The caspase-dependent pathway was assessed using western blot analysis. Results showed that berberine induced the apoptosis of liver cancer cells through procaspase-9, and its effector caspases, procaspase-3 and procaspase-7. Flow cytometry revealed that berberine caused cell cycle arrest at the M/G1 phase. The results of reverse transcription-polymerase chain reaction showed that berberine increased the expression of Bax, which resulted in the activation of the caspase cascade. The present findings demonstrated that berberine induces the apoptosis of Huh7 cells via the mitochondrial pathway.

Abstract 505: Jagged 2 knockdown inhibits invasion in colorectal cancer cell lines

Background: The notch pathway is involved in control of cell differentiation in various tissues including pancreas, muscle and bone marrow. Jagged 2 (JAG2) is a ligand for the notch pathway and was found to be overexpressed in malignant plasma cells from patients with multiple myeloma, causing the secretion and release of IL-6, VEGF, and IGF-1 in the microenvironment supporting myeloma cell growth. In breast cancers, it was found to be overexpressed at the hypoxic invasive front and was significantly correlated with metastasis free survival. Furthermore, up-regulation of JAG2 expression in mouse lung adenocarcinoma cells promoted its metastasis in mice. However, the expression pattern and function of JAG2 in colorectal cancer (CRC) is not clear. Therefore in this study, we examined the expression of JAG2 in CRC cell lines and determined the effect(s) of JAG2 knockdown by RNA interference in CRC cell lines. Materials and Methods: The expression of JAG2 protein was examined in four CRC cell lines (SW480, SW620, HCT116, DLD-1) and also in 1 normal colon epithelial cell line (CCD18co) using the western blot. To investigate the effects JAG2 knockdown in CRC cell lines, a pool of 4 siRNAs against JAG2 was transfected into the 4 CRC cell lines listed above. The effects on cell growth was then determined by the CellTiter 96® AQueous One Solution Cell Proliferation Assay (the MTS assay) and the Matrigel invasion assay was performed to assess its effects on invasive capability. Results: Western blot results showed that JAG2 protein was expressed in all 4 colorectal cancer cell lines including SW480, SW620, HCT116 and DLD-1 but not in the CCD18co normal colon epithelial cell line. The MTS assay showed that cell growth was not affected by JAG2 knockdown in the CRC cell lines. Interestingly, the invasive capability of HCT116 and DLD-1cells was reduced after JAG2 knockdown. Conclusions: Results from this study suggest that JAG2 may play a role in the invasiveness of CRC cell lines but not in cell proliferation. JAG2 may be a promising therapeutic target for inhibition of metastasis in colorectal cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 505. doi:1538-7445.AM2012-505

BAG3-related myofibrillar myopathy in a Chinese family

In contrast to the usual slow disease progression in myofibrillar myopathies, patients with Bag3opathy often have a rapidly progressive and more severe phenotype with a worse prognosis. We describe a Chinese patient, born to non-consanguineous parents, who first presented at age 6 with clumsy walking and difficult climbing staircase. With a history of restrictive lung disease previously diagnosed as asthma, she progressed rapidly with proximal myopathy, rigid spine and bilateral tightening of the Achilles tendons requiring surgical elongation. Hypertrophic cardiomyopathy with restrictive physiology was shown by echocardiogram. Moreover, prolonged QT interval was also noted in the patient. Family history was unremarkable yet her father was incidentally found to have prolonged QT interval. Mutation analysis with genomic DNA of the proband showed heterozygous de novo known mutation c.626C>T (p.Pro209Leu) and a germline variation c.772C>T (p.Arg258Trp) in BAG3. Her father was found to be a carrier of c.772C>T. Muscle biopsy findings were suggestive of myofibrillar myopathy on light microscopy and ultrastructural studies. To our knowledge, this is the first Chinese case of Bag3opathy so far reported.

The Use of Pulsed Dye Laser for the Prevention and Treatment of Hypertrophic Scars in Chinese Persons

BACKGROUND

Pulse dye laser has been used with variable degrees of success in the treatment of hypertrophic scars, and although earlier reports suggested a significant degree of improvement, more recent studies have raised concern about its effectiveness. Furthermore, most previous studies examined its use in patients with light skin types, and the use of pulse dye laser in dark-skinned patients for the treatment of hypertrophic scars is not well established.

OBJECTIVE

The objective was to assess the role of pulsed dye laser therapy in the treatment and prevention of hypertrophic scars in Chinese persons.

METHODS

Twenty-nine patients (35 scars) who had scars for less than 6 months were recruited into the prevention group, and 27 patients (36 scars) who had scars for more than 6 months were recruited into the treatment arm of the study. Each received pulse dye laser treatment (585 nm, 1.5-msec pulse duration, 5-mm spot size, 7-8 J/cm(2)) for three to six treatments at 8-week intervals. Half of the scar was treated with the laser and the other half was used as a control. All patients were assessed for subjective improvement with the use of a structured questionnaire and objectively with ultrasonography for thickness and a cutometer for viscoelasticity. Scars were marked on every patient and mapped with a translucent paper at the first appointment to ensure the consistency of location. At the end of the study, 15 patients from the prevention group (15 scars) and 23 patients from the treatment group (34 scars) agreed to return for spectrophotometer assessment.

RESULTS

Fifty-four percent of patients in the prevention group and 66% of patients in the treatment group considered their scars to be better or much better. For both groups of patients, there was significant improvement in term of pruritics after laser treatment. For objective assessment, although scar thickness reduced significantly compared to baseline in the treatment group, such change was not significant when changes in the control side were taken into consideration. There was insignificant change in viscoelasticity. Spectrophometer assessment indicated a significant degree of lightening in the treatment group.

CONCLUSION

Our study indicated that although there was significant symptomatic improvement, there was an insignificant degree of objective improvement in terms of scar thickness and viscoelasticity in the prevention group compared to the control group. Our findings are in line with several previous controlled studies and contradict the results of several others. Such differences can be due to differences in assessment methodology, laser settings, skin type, and scar location. Suprapurpuric pulsed dye laser should not be considered as the standard of practice for the treatment and prevention of hypertrophic surgical scars especially in the chest in Asians patients.

Tuberculous meningitis with spinal tuberculous arachnoiditis

This report is of a 36-year-old woman who initially presented with confusion and fever. Subsequent investigations showed tuberculous meningitis with acute hydrocephalus. Ventriculoperitoneal shunt was performed and anti-tuberculosis therapy was given. The patient was later noticed to have weakness of both lower limbs and urinary retention. Magnetic resonance imaging of the thoracic spine showed radiological features of tuberculous arachnoiditis with cord compression. Decompressive laminectomy was performed and high-dose systemic corticosteroid was given. A high level of awareness is required when diagnosing tuberculous arachnoiditis and the importance of high-dose corticosteroid in the treatment regimen is emphasised.

Before the paradigm shift: concepts and communication between doctors and nurses in a burns team

The evolution of care delivered by a multidisciplinary burns team is a function of the effectiveness of the professional communication between team members. In this exercise, we have explored concepts and communication between nurses and doctors in a burns team. Loosely structured weekly meetings were held over a 4-month period. The explicit objective was to determine and define the current model of burns care in a regional burn centre. The implicit objective, however, was to develop a mutual appreciation of actual and potential problems in communication. Consensus task identification was achieved at the end of each meeting with full compliance in completing the tasks before the next meeting. Although there was a unanimous commitment to the team concept, traditional, professional, paradigms persist. For nurses, the concept of holistic modelling predominated, whilst the disease centred paradigm remained the focus of medical modelling. Linguistic, cultural and professional barriers to effective communication were identified but did not readily conform to prior expectations. Experience in burns care can transcend these barriers more effectively than a common culture or profession. In conclusion, team work and team building is a complex process that can benefit from an ongoing process of re-evaluation. An obvious yet common error is to assume a level of mutual understanding that does not in fact exist. Stepping aside to re-explore fundamental principles on which team members base their personal and professional practice can help in elucidating and determining new paradigms of care, which can be evaluated and appropriately implemented. The consensus conclusion was that this approach was a very valuable investment in time in pursuing excellence in the field of burns care.

Chemical assaults in Hong Kong: a 10-year review

The aim of this study was to assess the patients admitted to Prince of Wales Hospital Burns Unit, Hong Kong between September 1991 and August 2001 following chemical assault. A total of 2319 burns were admitted during the study period of which 19 had been subjected to chemical assault. All victims sustained a burn injury to the head and neck area and 47% of victims' eyes were burnt. A total of 84% required surgical intervention. Where a reason for the attack was admitted most were due to relationship difficulties. This study has defined the victims of chemical assault in Hong Kong. At a time when the overall number of assaults in Hong Kong is at its lowest level for 5 years it is of concern that there appears to have been a recent increase in the number of chemical assaults in Hong Kong.

Outcome analysis of 286 severely burned patients: retrospective study

OBJECTIVE

To evaluate the outcomes of severely burned patients treated at a regional burns unit and to develop a predictive model for survival and length of hospital stay for major burn patients in Hong Kong.

DESIGN

Retrospective study.

SETTING

Burns unit of a regional public hospital, Hong Kong.

PATIENTS

Two hundred and eighty-six severely burned patients treated from March 1993 to February 2000.

MAIN OUTCOME MEASURES

Details of demographics, mechanism of burn, extent of burn, incidence of inhalation injury, length of hospital stay, and mortality rate were recorded and entered into a database. Stepwise logistic regression and linear regression were applied to develop a predictive model for mortality and morbidity, respectively.

RESULTS

Of 286 major burn patients treated in this 7-year period, 25 patients died from their injuries, yielding a mortality rate of 8.7%. Stepwise logistic regression was applied to develop a predictive model for mortality. We found that inhalation injury, age, and total body surface area involvement were independent significant predictors of death. Accuracy of this predictive model reached 93%. Similarly, stepwise linear regression was used to develop a predictive model for length of hospital stay. Sex, inhalation injury, total body surface area of burn, and total body surface area(2) of burn were significant predictors of length of hospital stay (R(2)=0.2). Only three patients' duration of hospital stay was more than three standard deviations from the predicted length of hospital stay.

CONCLUSION

A predictive model for mortality and length of hospital stay has been developed for major burn patients in Hong Kong. This model may help clinicians to counsel patients and relatives at an early stage of care, to provide a basis from which new treatment plans can be compared, and to facilitate efficient allocation of valuable medical resources.

Endoscopic-assisted subcutaneous mastectomy and axillary dissection with immediate mammary prosthesis reconstruction for early breast cancer

BACKGROUND

Endoscopic surgery has been applied successfully in breast lump excision, breast augmentation, subcutaneous mastectomy for gynecomastia, and axillary dissection. Since subcutaneous mastectomy has been proven to be oncologically safe for early breast cancer, we have sought to develop a reproducible minimally invasive endoscopic-assisted technique to address this condition.

METHODS

Between December 1998 and May 1999, endoscopic-assisted subcutaneous mastectomy and axillary dissection with immediate reconstruction using a mammary prosthesis was performed in nine patients with early breast cancer at the Prince of Wales Hospital, Hong Kong. A 5-cm skin incision was made along the line of the lowest axillary skin crease. Dissection was continued down to the lateral border of the pectoralis major muscle. A subpectoral pocket was gently created by an endoscopic breast dissector. The endoscopic breast retractor and 10-mm/30 degrees scope were introduced into the subpectoral pocket, and further dissection was carried out using a 7-in harmonic scalpel under endoscopic vision down to a level 1 cm caudal to the inframammary fold. This subpectoral space was used for the insertion of the mammary prosthesis later on. Endoscopic-assisted subcutaneous mastectomy was performed afterward. Combined level I and level II axillary dissection was carried out via the same incision under direct vision.

RESULTS

Apart from minor skin flap bruises in our first two patients, there were no major complications. Histological examination of all the specimens showed clear margins. Postoperative radiotherapy and chemotherapy were given in the usual manner. All patients were satisfied with the reconstructive outcome.

CONCLUSIONS

We have described a novel endoscopic technique for subcutaneous mastectomy with immediate mammary prosthesis reconstruction in treating early breast cancer patient. This technique can minimize skin incision, reduce blood loss, and improve reconstructive outcome. It is easy to learn and well accepted by patients.

An in vivo study comparing the efficacy and complications of diode laser and long-pulsed Nd:YAG laser in hair removal in Chinese patients

BACKGROUND

Lasers with long wavelengths are less well absorbed by melanin and are considered to be particularly suitable for hair removal in dark-skinned patients.

OBJECTIVE

To compare the efficacy and complications of 800 nm diode and long-pulsed 1064 nm Nd:YAG lasers in laser-assisted hair removal in Chinese patients.

METHODS

Fifteen women had hair removal treatments (13 axillae and 2 legs) with diode laser on one side and Nd:YAG laser on the other. They were followed up for 36 weeks. Subjective assessments included the degree of immediate pain and the degree of hair regrowth. Clinical photographs were taken for evaluation by two independent observers to assess complications and the degree of hair regrowth.

RESULTS

Long-pulsed Nd:YAG laser was found to be significantly associated with a greater degree of immediate pain after laser surgery (P =.0001, independent sample t-test) and also had a longer laser time (P =.0001, independent sample t-test). Besides transit adverse effects such as erythema and perifollicular edema, only one patient developed hypopigmentation at week 6 which resolved by week 36. Although regrowth rates were low at week 6 (subjective rates were 23% and 19% for Nd:YAG and diode laser, respectively), most patients had significant regrowth at week 36 (subjective regrowth rate 91% for both long-pulsed Nd:YAG and diode lasers).

CONCLUSION

Diode 800 nm and Nd:YAG 1064 nm lasers are safe in laser-assisted hair removal in Chinese patients, and besides immediate pain, there was no other significant adverse effect. Most patients experienced regrowth 36 weeks after a single treatment. Further study is necessary to determine the long-term clinical efficacy and complications of laser-assisted hair removal with these systems in dark-skinned patients.

A retrospective study on the efficacy and complications of Q-switched alexandrite laser in the treatment of acquired bilateral nevus of Ota-like macules

BACKGROUND

Acquired bilateral nevus of Ota-like macules (ABNOM), or Hori's macules, is a common Asian condition that is characterized by bluish hyperpigmentation in the bilateral malar regions. Unlike nevus of Ota, ABNOM is an acquired condition that often develops after 20 years of age and involves both sides of the face, but there is no mucosal involvement. Recently Q-switched (QS) 1064 nm Nd:YAG lasers have been effective in clearing this condition. The effectiveness of QS alexandrite lasers has not yet been studied.

OBJECTIVE

To retrospectively assess the efficacy and complications of QS alexandrite lasers in the treatment of ABNOM.

METHODS

Thirty-two Chinese women with ABNOM ranging in age from 28 to 66 years were involved in the study. All underwent QS alexandrite laser treatment (755 nm, spot size 3 mm, 8 J/cm(2)). Topical hydroquinone and tretinoin cream were given to those with hyperpigmentation after the laser surgery. Clinical photographs were taken before and after laser surgery and assessed by two independent observers. The degree of clearing was scored and complications, including hypopigmentation, hyperpigmentation, scarring, and erythema, were assessed.

RESULTS

The mean number of treatment sessions was 7 (range 2-11) and the mean treatment interval was 33 days. Both observers identified more than 80% of the patients as having more than a 50% degree of clearing, and complete clearance was seen in more than 28% of patients. Although most patients had postlaser hyperpigmentation and were on depigmentary regimes, the hyperpigmentation was seen in only 12.5% of the patients during photographic evaluation. Hypopigmentation was seen in 50% of patients and erythema in 41%.

CONCLUSION

QS alexandrite appears to be effective in the treatment of ABNOM. Postoperative pigmentary changes were frequent and the use of topical depigmentary agents was necessary to achieve a satisfactory result. Transient hypopigmentation risk was high, affecting up to 50% of the patients. Further study is warranted to compare the efficacy and complications of different laser systems in the treatment of this condition.

A prospective controlled clinical study of skin donor sites treated with a 1-4,2-acetamide-deoxy-B-D-glucan polymer: a preliminary report

The effect of Hyphecan (1-4,2-acetamide-deoxy-B-D-glucan) on skin donor site healing was compared with the standard skin donor site dressing Kaltostat (calcium sodium alginate) in 35 burn patients with 70 skin donor sites prospectively. The median time of wound healing for the Hyphecan group was 12 days with an average of 13.1+/-4.0 days (ranged from 9 to 28 days) while the Kaltostat group had a median healing time of 12 days (ranged from 8 to 28 days) with a mean of 13.0+/-4.1 days. The difference in healing time between these two groups was statistically insignificant with a P-value of 0.95. The infection rate was 2.9% for both Hyphecan and Kaltostat. These 35 patients had been followed up from 10 to 16 months and no difference in long-term donor site morbidity between Hyphecan and Kaltostat had been observed. This finding was encouraging because the cost of Hyphecan is less than 50% of Kaltostat and it may be worthwhile to explore the clinical application of Hyphecan in other area of burns treatment.

Odontogenic subperiosteal abscess of orbit: a case report

Subperiosteal abscess of orbit is an uncommon but serious complication of orbital infection. We report a case of a 78 year old gentleman who presented with bilateral periorbital oedema and proptosis. Computerised tomography of orbit revealed bilateral dilated superior ophthalmic veins. Bilateral carotid-cavernous fistula was initially suspected. Serial imaging showed an increasing bilateral subperiosteal lesion of the orbit. Fine needle aspiration confirmed subperiosteal abscess. A high level of awareness is necessary in diagnosing subperiosteal abscess.

Skin care in burn patients: a team approach

Skin care is an important but often neglected issue in burn management. Newly healed burn skin is fragile, itchy, dry, and susceptible to sunburn. Without proper skin care in burn patients, they may suffer from sleep and mood disturbances, depression, and poor compliance to treatment that can jeopardize the rehabilitation process. At the Prince of Wales Hospital, skin care has been managed since February 1996 by a team consisting of plastic surgeon, dermatologist, occupational therapist and nursing specialist. The purpose of this study was to evaluate the impact of a skin care program run by a Skin Care Team on the rehabilitation of burn patients in a tertiary burn centre. The role of different members of the team was also discussed.

Contact burn by charcoal in an attempted suicide

A 23-yr-old lady was inadvertently burned during an attempted suicide. After quarrelling with her boyfriend, she attempted to commit suicide by using alcohol, benzodiazepine and burning charcoal within her sealed bedroom. Her left leg fell over the edge of the bed while she was half-conscious, that resulted in direct contact with the hot pot causing 1% full thickness burn and burn of her left tibialis anterior and extensor digitorum longus. She was initially resuscitated with 100% oxygen and gastric lavage and subsequently was managed in the Burns Unit for wound care, surgical debridement of the burn wound and skin graft, and psychological support. Burning charcoal in a sealed room is an emerging form of suicide in Hong Kong and this is the first case complicated by a burn wound in our locality. A holistic approach to tackle the bio-psycho-social aspects of individual's problem is advocated.

Assault by burning--a reappraisal

Assault by burning is a serious form of trauma that often results in higher incidence of inhalation injury, longer intensive care unit (ICU) and hospital stay, and higher mortality rate than is observed in the general burn population. We evaluated the epidemiology and outcome of assault burn victims treated in a tertiary burn center over a 6-year period. Among the 1063 acute burn patients who had been admitted to the Burns Unit between March 1993 and February 1999, 28 (2.6%) had assault burn injuries either by scald, chemical or fire. The mean extent of burn was 21.9%+/-20.8% (range 2-90%) total body surface area and the mean length of hospital stay was 65.2+/-107.3 days (range 1-565). Nineteen out of 25 patients (67.9%) underwent 76 operations. Nine patients had inhalation injuries requiring intubation and ICU admission. Three patients died in the series, which yielded a mortality rate of 10.7%. Compared to the general burn population, the assault burn group had significantly larger burn size (P<0.001), higher incidence of inhalation injury (P<0.001), longer ICU and hospital stay (P<0.001), and higher mortality rate (P<0.005). When these 28 victims were grouped according to the type of assault burn injury into a fire group, chemical group and scald group, all the 9 ICU admission and the 3 mortalities belonged to the fire group. Assault by fire resulted in larger burn size (P=0.03), more inhalation injury (P<0.001) and longer ICU stay (P=0.02). Although the fire group had a longer hospital stay and higher mortality rate, this was statistically insignificant.

A study of burn injuries in the elderly in a regional burn centre

We evaluated the epidemiology and outcome of 94 elderly burn patients of age 60 years or older treated in a local burn centre over a period of 6 years. There were 44 males and 50 females with a male to female ratio of 0.88 and an average age of 73.8+/-9 years. The mean extent of burn was 13.3+/-18.4% total body surface area (TBSA) with 14 patients (15%) suffering from a burn size >20% TBSA. The vast majority of injuries (90%) occurred at home. Scalds resulted in 62 admissions (66%) and flame burns accounted for another 29 admissions (31%). The burns predominantly involved the extremities and the trunk. Four patients had inhalation injuries and required admission to the Intensive Care Unit for ventilatory support. The majority of patients (60%) did not require any operations. The mean hospital stay of the survivors was 30.1+/-34.1 days and 35% of them stayed less than 2 weeks. Fifty-five patients (59%) had at least one pre-existing medical problem requiring long-term medication and 41 patients (44%) were living alone. Sixty-three patients (67%) presented more than 8 h after the burn injuries and 34 patients (36.2%) had no first aid treatment of their burn wounds. In addition, 40 patients (42.5%) had their wounds treated inappropriately. Seven patients died in this series which yielded a mortality rate of 7.4%. The outcomes of early versus late excision and grafting were also analyzed.

An analysis of 550 hospitalized pediatric burn patients in Hong Kong

A total of 550 acute burn patients under the age of 15 years were admitted to the Burns Unit of Prince of Wales Hospital, Hong Kong between March 1993 and February 1999. There were 337 males and 213 females with a male to female ratio of 1.58:1. The median age was 2.5 years and the median burn size was 5% total body surface area (TBSA). Toddlers of age < 2 years accounted for 235 (42.7%) of admission. Domestic burns resulted in 481 (87.5%) injuries followed by play-related burns that caused 34 (6.2%) admissions. Scalding was the most common cause of injury, which accounted for 497 (90.4%) admissions, followed by flame burns, which resulted in 45 (8.2%) injuries. Nine patients (1.6%) had inhalation injury requiring intubation and ventilatory support. The median hospital stay was 8 days and there was no seasonal variation in admission. The majority of patients (80.2%) had their wounds healed without any operation. Only 19 out of 550 patients (3.5%) had burns of 30% TBSA or larger, and only nine patients (1.9%) had inhalation injuries. Only one patient died in this series, which yielded a mortality rate of 0.2%.

A prospective study of the effect of botulinum toxin A on masseteric muscle hypertrophy with ultrasonographic and electromyographic measurement

We evaluated the effect of botulinum toxin A on masseteric muscle hypertrophy by using ultrasound and electromyography. Five patients (four with bilateral and one with unilateral masseteric muscle hypertrophy) were studied prospectively. In each patient, ultrasound-guided percutaneous intramuscular injection of botulinum toxin A was carried out. The change in muscle bulk was evaluated using serial ultrasonography and the electrical activity was assessed with electromyography. All five patients (nine hypertrophic muscles) showed a good response, with the maximal effect of a 31% reduction in muscle bulk seen 3 months after treatment. The effect remained stable one year after injection for six of the hypertrophic muscles, whereas three muscles needed a second injection to maintain the atrophy. This preliminary prospective study suggests that botulinum toxin A is a safe alternative method of treating masseteric muscle hypertrophy. However, the effect may be temporary and further intramuscular injection may be required to maintain atrophy.

Effect of the blood substitute diaspirin crosslinked hemoglobin in rat mesenteric and human radial collateral arteries

The actions of the blood substitute diaspirin crosslinked hemoglobin (DCLHb) were investigated in rat (small mesenteric artery) and human (radial collateral artery) resistance vessels mounted in a wire myograph for isometric tension recording. DCLHb did not contract resting vessels from rats, but vasoconstrictor responses were observed in isolated arteries and perfused mesenteric beds prestimulated with threshold concentrations of methoxamine. The DCLHb contractile responses were greatly attenuated by N(G)-nitro-L-arginine methyl ester hydrochloride (L-NAME) or endothelial removal, whereas BQ-123 (endothelin A receptor antagonist), prazosin (alpha1-adrenoceptor antagonist), or indomethacin (cyclooxygenase inhibitor) had no effect. Endothelium-dependent relaxations to carbachol in both rat mesenteric and human radial collateral artery were inhibited by DCLHb. Relaxations to carbachol were studied in the presence of L-NAME or 25 mM KCl to investigate the effect of DCLHb on endothelium-derived hyperpolarizing factor (EDHF) and nitric oxide, respectively. In both rat and human vessels, EDHF-mediated relaxations were not affected by DCLHb preincubation, whereas the nitric oxide component of carbachol-induced relaxations was practically abolished. In conclusion, inhibition of the effects of basal nitric oxide release underpins the vasoconstrictor effects of DCLHb. DCLHb effectively abolishes the nitric oxide component of carbachol-induced relaxation, with no effect on the EDHF-mediated component in both isolated rat mesenteric and human radial collateral arteries.

Management of paraffinoma of the breast: 10 years' experience

Paraffin injection was regarded as a simple and effective method of improving body contour. It was widely used in breast augmentation until the long-term complication of paraffinoma was recognised. Paraffinoma of the breast can present as a spectrum of disease ranging from a painless mass to a destructive ulcer simulating breast cancer. This makes it difficult to make the correct diagnosis and provide suitable treatment. Eight patients with paraffinoma of the breast have been managed at a teaching hospital over a 10 year period. All were females, with a mean age of 65.6 years (range: 57-73 years). The average time between paraffin injection and the onset of symptoms was 24 years (range: 11-30 years). These patients have been followed up for between 3 and 10 years (mean: 6.1 years). One patient died of congestive heart failure 4 years after bilateral mastectomy for painful paraffinomas of the breasts. Another patient had a coexisting infiltrative ductal carcinoma of the breast. The clinical presentations, radiological appearances, histopathological features and the treatment are discussed.

Suicidal burns in Hong Kong Chinese

There were 1063 acute burn patients admitted to the Burns Unit of Prince of Wales Hospital, Hong Kong, between March 1993 and February 1999. Eleven patients (1%) were burned due to attempted suicide. Seven were males and four were females, with a male:female ratio of 1.75:1. The median age was 38 years (range: 20-49 years) and the median extent of the burns was 55% total body surface area (range: 1-95%). Ten patients (90.9%) were self-incinerated and one patient attempted suicide by jumping into a hot bath. Seven patients (63.6%) suffered from severe smoke inhalation injury that required immediate intubation for ventilatory support. The average number of operations for the survivors was 3.7 (range: 0-8) and their median hospital stay was 42 days (range: 2-92 days). Four patients (36.4%) died from their injuries. Suicidal burns were more common among unemployed males with a history of psychiatric illness and substance abuse. Town gas (naphtha: a mixture of 49% hydrogen, 28.5% methane, 19.5% carbon dioxide and 3.0% carbon monoxide) was the most frequently used agent for self-immolation because it is probably the most convenient source of a fire accelerant in Hong Kong. Compared to the general burn population, this suicide group had a larger extent of burns, higher incidence of inhalation injury, required more operative treatment and longer hospital stay with a higher mortality rate.

An epidemiological study of 1063 hospitalized burn patients in a tertiary burns centre in Hong Kong

A total of 1063 acute burn patients were admitted to the Burns Unit of Prince of Wales Hospital, Hong Kong between March 1993 and February 1999. There were 678 males and 385 females with a male to female ratio of 1.76:1. The median age was 13.1 year-old and the median burn size was 6% total body surface area (TBSA). Pediatric patients under the age of 15 year-old accounted for 550 (51.7%) admissions and 235 (42.7%) of them were toddlers <2 year-old, while adult patients of age above 15 year-old accounted for the other 513 (48.3%) admissions. There was no seasonal variation in admission. Domestic burns resulted in 756 (71.1%) injuries followed by industrial burns that caused 175 (16.5%) admissions. The median hospital stay was 9 days and 54 patients (5.1%) had inhalation injury requiring intubation and ventilatory support. Twenty-four patients died in this series which yielded a mortality rate of 2.3%. The median age for this mortality group was 46.6 year-olds with a median extent of burns of 68% TBSA. There were 16 males and 8 females with a male to female ratio of 2:1. Eighteen (75%) patients had flame burns and 15 (83.3%) of them had inhalation injury. The mortality group had significantly larger burn size (P<0.001), higher incidence of inhalation injury (P<0.001) and older age (P<0.001) compared to the survivors.

Playing with fire--a significant cause of burn injury in children

We report our experience with 50 patients who were burned as a result of playing with fire over the period of January 1993 to December 1999. There were 43 males and 7 females with a male to female ratio of 6.1:1. The average age was 12.3+/-10.3 year with 39 (78%) patients under the age of 15. The mean extent of burn was 6.4+/-10.7% total body surface area (TBSA) and 2 children had extensive burns >30%. The burns predominantly involved the head and neck region, upper limb, hand and lower limb. There was no mortality in our series. Wax and fireworks were recognized as the two major burn causing agents in these 50 patients. Risk factors associated with these injuries as well as preventive measures were also presented.

Corneal perforation with extrusion of lens in a burn patient

The incidence of ophthalmologic injuries has been reported to be between 20 and 25% in all the burn patients. As most of the eye injuries are associated with severe burns, attention is often directed towards the life-threatening events and eye injuries may be overlooked and undertreated. This case report presents a patient who had 40% flame burn and had recently been transferred from another hospital. He was examined by an ophthalmologist at the referring hospital and it was documented that both of his eyes were normal. He was transferred into the Burns Unit at the Prince of Wales Hospital 8 h later. Unfortunately, all the attention was directed to save his life and it was not until post-burn day 11 that he was found to have right corneal ulceration. Despite vigorous ophthalmologic treatment, the cornea perforated 2 days later with subsequent extrusion of the lens. In view of his grave prognosis with multi-organ failure, he was treated conservatively and he died the following day. It is mandatory to refer patients with facial burns to the ophthalmologist for ocular examination. We recommend that serial eye examinations should be carried out in burn patients who are unconscious or intubated for ventilatory support even if the initial ophthalmologic examinations are normal as the potential risk of serious ocular injuries are high in this particular group of patients.

Iatrogenic burn caused by an alcohol lamp

Iatrogenic injury is an intrinsic risk of all medical procedures. Various kinds of iatrogenic complications have been extensively reported and recognized. Two patients were referred to the Prince of Wales Hospital for iatrogenic flame burn caused by the breakage of an alcohol lamp during ENT examination. They were 8 and 9 years old and sustained 12 and 17% intermediate to deep dermal burns respectively. There was no eye or inhalation injury. They were treated initially at the referring hospital. Despite having the best possible treatment, the parents were hostile to and demanding of the medical attendants and the patients were uncooperative throughout the whole treatment period. Rehabilitation of the two children was jeopardized. The situation was very difficult when they were first seen at the Prince of Wales Hospital. The burn surgeon at the Prince of Wales Hospital, as a third party, managed to act as a bridge between the referring hospital and the patients and their families. Several meetings were held and the best interests of the two patients was addressed. The compensation issue was also settled without formal legal prosecution.

A retrospective analysis of complications in the treatment of nevus of Ota with the Q-switched alexandrite and Q-switched Nd:YAG lasers

BACKGROUND

Studies on the use of Q-switched alexandrite (QS alex) and QS Nd:YAG lasers in the treatment of nevus of Ota were limited to case reports and small series. There was no study that looked at the complication rate of these systems.

OBJECTIVE

To retrospectively study the complication rate of nevus of Ota patients that were treated with QS alex laser, QS Nd:YAG laser, or a combination of both.

METHODS

The study was performed in a teaching hospital and a private hospital, where 513 patients with nevus of Ota had been treated since 1993. The 171 patients with 211 treatment sites were evaluated retrospectively following treatment with QS alex laser only (n = 58), QS Nd:YAG laser (n = 105) only, or a combination of both systems (n = 48). Patients were called back to be interviewed and examined by two independent clinicians to look for evidence of complications.

RESULTS

Of the treatment sites, 15. 3% had hypopigmentation, 2.9% had hyperpigmentation, and texture changes and scarring were seen in 2.9% and 1.9%, respectively. The combined treatment group was associated with a significantly higher risk of complications. Thirteen patients had recurrence of their nevus after complete or near-complete clearance with laser treatment.

CONCLUSION

Hypopigmentation is common after the use of QS laser for lightening of nevus of Ota. This particularly applies when alternate treatment with QS alex and QS Nd:YAG is used. Recurrence is an important issue and must be taken into consideration, especially when children are treated.

An in vivo trial comparing the clinical efficacy and complications of Q-switched 755 nm alexandrite and Q-switched 1064 nm Nd:YAG lasers in the treatment of nevus of Ota

BACKGROUND

Q-switched 755 nm alexandrite (QS alex) and Q-switched 1064 nm Nd:YAG lasers are effective in the treatment of nevus of Ota. Our previous in vivo study indicated that patients better tolerate QS alex than QS 1064 nm Nd:YAG laser. However, in terms of clinical efficacy and long-term complications, the study did not indicate which laser is superior. Although both machines may appear to be similar in effectiveness, the low number of treatment sessions may contribute to this apparent lack of difference.

OBJECTIVE

The aim of this study was to compare the clinical efficacy and complications of QS 755 nm alex and QS 1064 nm Nd:YAG lasers in the treatment of nevus of Ota after three or more treatment sessions.

METHOD

Forty patients were recruited for this study and all had received three or more laser treatment sessions with an interval of at least 2 months between each. Half of the lesion was treated with QS alex and the other half with QS 1064 nm Nd:YAG laser. The degree of lightening was assessed subjectively by the patient using a visual analog scale and objectively by two independent clinicians. Patients were called back to be examined for evidence of complications.

RESULTS

In terms of subjective degree of lightening, QS 1064 nm Nd:YAG laser was found to be significantly more efficacious than QS alex (P = 0.018). Both clinicians also found QS 1064 nm Nd:YAG laser to be more effective, but statistical significance was only detected in one, not both of their scores (P = 0.005 and 0.414 for observers 1 and 2, respectively). More patients that received QS Alex developed complications (4 for QS alex and 2 for QS Nd:YAG), but the difference was not statistically significant.

CONCLUSION

QS 1064 nm Nd:YAG laser appears to be more effective than QS alex in the lightening of nevus of Ota after three or more laser treatment sessions. However, the majority (55%) of the patients reported no differences in results between the two lasers, and only one of the two observers noted statistically significant improvement of QS 1064 nm Nd:YAG over QS alex.

Bizarre paediatric facial burns

Child abuse and neglect account for a significant number of paediatric burn injuries. It is of great importance because of the high mortality, high frequency of repeated abuse, as well as the physical, psychological and social sequelae that it causes. Burn abuse is often under-recognized and under-reported because it is difficult to define non-accidental injury. On the other hand, false accusation of burn abuse is extremely damaging to the family. Bizarre and unusual burn injuries can be caused by accident and should not automatically be assumed to be deliberate injury. Three boys of age 1-7 years with bizarre facial burns were admitted to the Burns Unit at the Prince of Wales Hospital between February 1995 and July 1999. One was burned by his baby-sitter with hot water steam and the other two were burned by their mothers with hot boiled eggs. The unusual causes of their burns raised the suspicion of child abuse and formal investigations were carried out by the Social Services Department. Detail assessment including a developmental history of the child and the psychosocial assessment of the family revealed that these three boys were burned because of poor medical advice and innocent cultural belief.

In vivo trial comparing patients' tolerance of Q-switched Alexandrite (QS Alex) and Q-switched neodymium:yttrium-aluminum-garnet (QS Nd:YAG) lasers in the treatment of nevus of Ota

BACKGROUND AND OBJECTIVES

Different types of Q-switched lasers have been found to be effective in the treatment of nevus of Ota. However, a clinical trial involving in vivo comparison of the use of different laser systems has not been performed. The aim of the present study was to compare the patient tolerance of Q-switched Alexandrite (QS Alex) and Q-switched neodymium:yttrium-aluminum-garnet (QS Nd:YAG) lasers in the treatment of nevus of Ota.

STUDY DESIGN/MATERIALS AND METHODS

Thirty-three patients (11 male, 22 female) were recruited for this study, and 45 treatment sessions were performed. Half of each lesion was treated with QS Alex and the other half with QS Nd:YAG laser. Patients were interviewed with a visual analog scale questionnaire immediately after treatment and 1 week later. Questions included the degree of pain, swelling, and bleeding.

RESULTS

The immediate pain after treatment was more severe for QS Alex than for QS Nd:YAG laser. However, 1 week after laser therapy, most patients found QS Alex to be superior.

CONCLUSION

Patients tolerate QS-Alex better than QS Nd:YAG. This finding is important because patients with nevus of Ota are often children, and multiple laser sessions are necessary for complete resolution of the lesion.

The use of liposucker for spleen retrieval after laparoscopic splenectomy

The retrieval of spleen after laparoscopic splenectomy has long been a problem. Frequently, it is necessary to extend the wound for retrieving the spleen intact and to prevent potential spillage of splenic tissue into the peritoneal cavity. We describe the application of the liposuction unit to remove the spleen piecemeal after laparoscopic splenectomy. We have found this technique easy to apply and safe, without the necessity of excessive wound extension, while preserving splenic tissue for histologic examination.

Burn injuries during paint thinner sniffing

Thinner sniffing is popular among school children in Asian countries because it is readily available at low cost. Besides its toxicity to major organs, thinner inhalation is associated with various burn accidents. Four teenagers were admitted to the Burns Unit of the Prince of Wales Hospital over the period of 1996-1997. They sustained 3-25% TBSA flame burn and two of them had inhalation injuries as a result of the ignition of a cigarette during thinner sniffing. None of them had evidence of thinner intoxication as shown by blood tests. In the management of their acute burn injuries, their hidden social and family problems were explored. With the cooperation of different disciplines, early psychosocial intervention was given and their behavioral and psychological disturbances were successfully managed.

Single-dose tropisetron for preventing postoperative nausea and vomiting after breast surgery

In this randomized, double-blind, placebo-controlled study, we compared the efficacy of tropisetron 5 mg with tropisetron 2 mg for the prevention of postoperative nausea and vomiting (PONV) after breast surgery. One hundred forty-eight female patients were randomized to receive either tropisetron 5 mg (n = 49), tropisetron 2 mg (n = 49), or saline (n = 50) before the induction of anesthesia with thiopental and morphine. Anesthesia was maintained with nitrous oxide and isoflurane. Postoperative analgesia was provided by patient-controlled analgesia with i.v. morphine. The incidence of PONV, the pain score, and the analgesic requirement were recorded for 48 h. There was no difference among groups in patient characteristics, risk factors for PONV, morphine consumption, or side effects. During the first 6 h postoperatively, the incidence of PONV after tropisetron 2 mg and 5 mg were similar and were superior to placebo (P < 0.001). After 6 h, the incidence of PONV increased significantly in patients who had received tropisetron 2 mg (P = 0.01) and was greater than that in patients who had received tropisetron 5 mg (P = 0.001). We conclude that single-dose tropisetron 5 mg is more effective than tropisetron 2 mg in the prevention of PONV after breast surgery.

IMPLICATIONS

Breast surgery is associated with a high incidence of postoperative nausea and vomiting. A single dose of i.v. tropisetron 5 mg is well tolerated and decreases the number of vomiting and nausea episodes after surgery.

Boiling wax burn in mid-autumn festival in Hong Kong

An unusual cause of burn, contact with boiling wax by children and adolescents during the annual mid-autumn festival in Hong Kong is presented. 57 patients who suffered from hot wax burn over the period 1986-1996 were admitted to the Burns Unit of the Prince of Wales Hospital. This special burn should be preventable by public education.

Evaluation of artificial skin (Integra) in a rodent model

The biocompatibility of artificial skin (Integra) has been investigated in clean surgical wounds of 20 guinea-pigs. A rectangular 3 x 3 cm full-thickness skin defect with excision carried down to the panniculus carnosus was prepared on the dorsal area of the guinea-pig. A thin layer of silver sulfadiazine cream was applied and artificial skin was placed to cover the wound. At day 14, the uppermost silicone layer was removed. Good take of the artificial skin was observed in 18 of 20 animals. Microscopy showed good vascular ingrowth in 14 of the 18 animals. The remaining four animals showed necrotic tissue, absence of vascularization and haemorrhage in the wound bed. Two of the 20 wounds showed purulent discharge. In this animal model, clinical 'take' of the neodermis was achieved in 18/20 animals (90 per cent), while vascular ingrowth was observed in only 14/20 animals (70 per cent). These results suggested that artificial skin in clean surgical wound is readily biologically incorporated into surrounding viable tissue.

Paraffinomas of the breast: mammographic, ultrasonographic and radiographic appearances with clinical and histopathological correlation

Paraffinomas are uncommon lesions occasionally encountered in the breast. The clinical and radiological (mammographic, ultrasound and plain film) features are presented in five patients with breast paraffinomas, one of whom had synchronous infiltrative ductal carcinoma. Histopathological correlation was available in two patients. Women with a history of paraffin injections into the breast may present decades later with hard, nodular breast masses simulating breast cancer. Dense fibrosis particularly in the retroglandular midbreast region causing streaky opacities and bizarre architectural distortion on mammography suggests the diagnosis. Flocculent, amorphous, ring or rounded calcifications may also be present within the breast and axilla. Migration of liquid paraffin through the tissue planes can result in diffuse conglomerate calcification in the chest and abdominal walls.

[Destructive paraffinoma of the breast and thoracic wall caused by paraffin injection for mammary increase. Apropos of 3 cases with review of the literature]

The injection of a high viscosity fluids into the tissues for cosmetic body contouring has been practised in the last four decades in the East and South-East of Asia. The injection of liquid paraffin for mammary augmentation was widely practised by surgeons, physician and even non medical people. Unfortunately, most of these cases ended by having different varieties of paraffinoma as a complication of a foreign body reaction. We report three cases of a destructive form of these paraffinomas ulcerating into both breasts and the anterior chest wall. One case was treated by bilateral mastectomy, radical excision of the anterior chest wall soft tissue and reconstruction by a vertical Rectus Abdominus Myocutaneous Flap. The second case had bilateral mastectomy and followed up for facial paraffinomas. The third case was just followed for up regular wound care as surgery was not indicated due to advanced age, poor general condition and the family request.

Amoxycillin and clavulanic acid versus cefotaxime and metronidazole as antibiotic prophylaxis in elective colorectal resectional surgery

In a prospective randomised controlled trial, amoxycillin plus clavulanic acid was compared to a combination of cefotaxime and metronidazole as prophylactic antibiotics in 164 patients who underwent elective colorectal resectional surgery. Wound infection occurred in 15 patients (9.1%) and deep surgical infection in 4 (2.4%). Seven cases of wound infection and 2 cases of deep infection occurred in the amoxycillin plus clavulanic acid arm, while 8 cases of wound infection and 2 cases of deep infection occurred in the cefotaxime plus metronidazole arm. Eighty-eight percent of infections occurred in patients who had low anterior resection or abdominoperineal resection of the rectum. Both the amoxycillin plus clavulanic acid and the combination of cefotaxime and metronidazole offer the same degree of protection against post-operative infection. The use of amoxycillin plus clavulanic acid as antibiotic prophylaxis is recommended because of its easier use and cheaper cost.

Model pores of molecular dimension. The preparation and characterization of track-etched membranes

Extremely uniform pores of near molecular dimension can be formed by the irradiation-etching technique first demonstrated by Price and Walker. The technique has now been developed to the stage where it can be used to fabricate model membranes for examining the various steric, hydrodynamic, and electrodynamic phenomena encountered in transport through molecular-size pores. Methods for preparing and characterizing membranes with pores as small as 25 A (radius) are described in this paper. Results on pore size determination via Knudsen gas flow and electrolyte conduction are compared. Pore wall modification by monolayer deposition is also discussed.