Short segment posterior instrumentation, reduction and fusion of unstable thoracolumbar burst fractures--a review of 26 cases

From January 1994 to January 1998, 26 patients of unstable thoracolumbar burst fracture were treated by a short segment posterior instrumentation (pedicular screw plate/rod system), reduction and fusion in Kuala Lumpur and Universiti Kebangsaan Malaysia Hospital. Majority of them were young and in a productive age group (mean age were 30 year-old). The mean duration of follow-up was 24.4 months. The injuries were caused by fall from height (69%) and motor vehicle accident (31%). Most of the fracture occurred at 1st and 2nd lumbar vertebrae (24/26). Twelve of the patients did not have neurological deficits. Out of 14 patients with neurological deficits, 64.4% of them showed an improvement of at least one Frankel's grade. There was no defect correlation between canal compromise and neurological deficit. Kyphotic angle improved from 20 degrees to 7 degrees immediately after surgery. In the last follow-up average kyphotic angle was 9 degrees with average lost of 2 degrees. The average length of hospitalization following surgery was 24 days. A posterolateral bony fusion was achieved in all cases at an average of 3 months. Complication included 2 loosening and 3 misplacement of pedicle screw fixation. We concluded that short-segment fixation with posterolateral decompression and fusion is effective in the treatment of unstable thoracolumbar burst fracture.

Gamma-scintigraphic study of the gastrointestinal transit and in vivo dissolution of a controlled release diclofenac sodium formulation in xanthan gum matrices

A xanthan gum matrix controlled release tablet formulation containing diclofenac sodium was evaluated in vitro and was found to release the drug at a uniform rate. The gastrointestinal transit behaviour of the formulation as determined by gamma scintigraphy, using healthy male volunteers under fasted and fed conditions, indicated that gastric emptying was delayed with food intake. In contrast, the small intestinal transit remained practically unchanged under both food statuses. Therefore, the delay in caecal arrival observed in the fed state can be attributed to the delay in gastric emptying. Rate of diclofenac sodium absorption was generally higher in the fed state compared to the fasted state, however the total amount absorbed under both food statuses remained practically the same. The rate of in vivo dissolution of the drug in the fed state was faster compared to that in the fasted state. Thus, at the time of caecal arrival, in vivo dissolution was complete in the fed state, unlike in the fasted state, where almost 60% of the drug was delivered to the colon.

Successful treatment of Candida albicans endocarditis in a child with leukemia--a case report and review of the literature

Candida species is now being increasingly recognised as an important cause of endocarditis especially in immunocompromised patients. A case of Candida albicans endocarditis in a child with acute lymphoblastic leukemia (ALL) is reported. The child did not have a central venous catheter at any time. Treatment consisted of intravenous amphotericin B and fluconazole for 3 weeks followed by oral fluconazole for 2 weeks. No surgical resection was necessary. We highlight here the importance of echocardiography in the management of prolonged febrile neutropenia and discuss the dilemma of continuing chemotherapy in such patients.

Salmonella meningitis and its complications in infants

OBJECTIVE

To review the presenting features, complications and outcome of infants with Salmonella meningitis.

METHODOLOGY

Retrospective review of all cultures of cerebrospinal fluid positive for bacteria in children below 12 years of age, processed at the Department of Medical Microbiology, University of Malaya Medical Centre, Kuala Lumpur from 1973 to 1997. Records of all cases positive for Salmonella species were retrieved and studied.

RESULTS

Thirteen infants aged 3 days to 9 months with Salmonella meningitis were included. The median age of onset of symptoms was 4 months. The clinical and laboratory features were similar to other causes of bacterial meningitis. Salmonella enteritidis was the commonest serotype isolated. Nine infants developed fits, six of which were difficult to control. Other complications noted were hydrocephalus (five), subdural effusions (four), empyema (three), ventriculitis (two), intracranial haemorrhage and cerebral abscess (one each). The use of ampicillin and/or chloramphenicol and inadequate duration of therapy resulted in recrudescence or relapse in five infants. The overall mortality was 18%. The presence of empyema, intracerebral abscess, ventriculitis, hydrocephalus, and intracranial haemorrhage were associated with adverse neurodevelopmental sequelae or death. More than half of those who survived had normal long-term outcome.

CONCLUSION

Infants who developed neurological complications as a result of Salmonella meningitis had significant mortality and adverse long-term neurodevelopment outcome.

Real-time intraoperative transesophageal echocardiography--how useful? Experience of 5,016 cases

OBJECTIVE

To evaluate transesophageal echocardiography (TEE) as an intraoperative monitoring modality and to assess its safety, reliability, and overall utility in real-time use during cardiac surgery.

DESIGN

Prospective, observational cohort study performed from January 1993 to June 1997.

SETTING

Operating room of a tertiary care hospital for cardiology and cardiovascular surgery.

PARTICIPANTS

Five thousand and sixteen adult patients with acquired heart disease, who underwent 1,356 valve procedures and 3,660 coronary artery bypass graftings (CABGs).

INTERVENTIONS

All patients were monitored with radial artery and pulmonary artery catheters, along with continuous TEE monitoring with a multiplane transducer.

MEASUREMENTS AND MAIN RESULTS

Prebypass imaging yielded unsuspected findings that either helped or modified the surgical plan in 158 of 1,356 valve procedures (11.65%) and in 993 of 3,660 CABGs (27.13%). There were 3,217 TEE-guided hemodynamic interventions in 944 patients (25.79%) in the CABG group and 629 in 142 patients (10.47%) in the valve group. TEE was the sole guiding factor in initiating therapy in 23.53% of events, whereas it was supportive to other monitoring modalities in 76.46% of events. Postbypass TEE identified the need for graft revision in 29 patients (0.8%), intra-aortic balloon pump (IABP) requirement in 29 patients (0.8%), and inadequate valve repair in 28 patients (2.08%). For the entire series, 38.78% of patients benefited from prebypass and 39.16% from postbypass use of TEE. There were no complications attributable to the use of TEE in the entire series. There was 87% concordance between online interpretation by a trained anesthesiologist and offline analysis by a cardiologist.

CONCLUSION

Intraoperative TEE is useful in formulating the surgical plan, guiding various hemodynamic interventions, and assessing the immediate results of surgery. It is safe and the results are reliable in the hands of trained anesthesiologists.

A review of haematogenous osteomyelitis in children in Kuala Lumpur Hospital

We review 81 cases of acute haematogenous osteomyelitis from 1983 to 1990 to establish current pattern of clinical presentation, modes of treatment and success of therapy. Majority of the patient (70%) presented within a week of symptom and significant number of them came with fever and swelling of the affected limb. Sedimentation rate was found to be raised in all of them. Fifty-four (55%) of them were treated surgically. The average antibiotic time was one week by intravenous administration followed by additional oral therapy for period up to four weeks. Average follow-up was 9 months. Six of them (7.5%) end up with various complication which was believed to be due to delay in getting medical treatment.

Characterisation of a chromatographically produced anti-D immunoglobulin product

A chromatographic fractionation method has been developed for the production of a liquid-stable anti-D immunoglobulin product for intravenous and intramuscular use. An immunoglobulin fraction, highly enriched with anti-D immunoglobulins, was isolated by cation-exchange column chromatography and further polished, first by anion-exchange chromatography, followed by an aluminium hydroxide gel treatment. The process includes two specific steps for virus inactivation and removal, namely S/D treatment and nanofiltration. The overall anti-D process yield is about 56%. The final product is stabilised with human albumin and glycine and placed in ready-to-use syringes. The anti-D product was shown to be stable in liquid state for at least 30 months at 4 degrees C.

A new technique for treatment of simple post-prostatectomy urinary incontinence: preliminary experience

PURPOSE

Because of the complexity of reconstructive surgical techniques, the high failure rate and cost of the devices used, as well as the associated mechanical malfunctions there is need for an alternative operation to treat post-prostatectomy urinary incontinence. We present a new procedure along with promising results in cases of simple post-prostatectomy incontinence after transurethral resection of the prostate or open prostatectomy.

MATERIALS AND METHODS

The principles of our technique include lysis of the pelvic urethra with preservation of the neurovascular bundle, as well as suspension of the prostatic capsule to the anterior abdominal wall. With this technique we corrected post-prostatectomy sphincteric incompetence in 21 patients. Preoperative evaluation included physical examination, excretory urography, ascending urethrocystography and urethrocystoscopy. Urodynamic investigations included uroflowmetry, cystometrography and urethral pressure profilometry. The patients were reevaluated radiologically and urodynamically 3 months postoperatively. Mean followup was 19 months.

RESULTS

All patients tolerated the procedure well. Few intraoperative and postoperative complications were encountered. The success rate was 81% and these 17 patients became continent day and night.

CONCLUSIONS

Our procedure combines the continence enhancing features of pelvic urethral elongation, urethral suspension, angulation of the prostatomembranous junction and prostatic fixation. The preliminary success rate of this technique is encouraging. However, larger numbers of patients and long-term followup are needed to confirm our findings.

Virus inactivation by pepsin treatment at pH 4 of IgG solutions: factors affecting the rate of virus inactivation

BACKGROUND

IgG preparations have rarely transmitted infectious diseases; however, because such transmission has occurred a few times, manufacturers are required to present experimental proof that their specific production process removes and/or inactivates viruses that may be present in the starting material.

STUDY DESIGN AND METHODS

The kinetics of virus inactivation mediated by pepsin treatment at pH 4 during the production of intravenous immunoglobulin was assessed with spiking experiments using human immunodeficiency virus, bovine viral diarrhea virus, Semliki Forest virus, and pseudorabies virus. The influence of various factors on the rate of virus inactivation also was studied by modifying the composition of the IgG solutions with respect to IgG, sucrose, and NaCl content.

RESULTS

Virus inactivation at 37 degrees C was extremely rapid and resulted in a complete loss of infectivity within 5 minutes to 1 hour. Inactivation was much slower at lower temperatures. Furthermore, inactivation was dependent on the solute composition. Increasing the sucrose content from 0 to 15 percent reduced the rate of inactivation of pseudorabies virus but did not affect the rate of inactivation of Semliki Forest virus. In contrast, increasing the NaCl content from 0 to 150 mM resulted in a reduction in the rate of inactivation of Semliki Forest virus, whereas the rate of inactivation of pseudorabies virus remained unaffected. Moreover, increasing the IgG concentration from 0 to 10 percent resulted in an increased rate of inactivation of pseudorabies virus but a decreased rate of inactivation of Semliki Forest virus.

CONCLUSION

Inactivation of viruses by pepsin treatment at pH 4 essentially is temperature-dependent, and the reaction rate is selectively influenced by the solute composition of the IgG solution. This has to be taken into account when safety data for different products are compared.

Hyperplasia of thymic gland

Hyperplasia of the thymus is the most common anterior mediastinal mass in infants. It is however exceedingly difficult to evaluate by the weight of the gland as it continues to grow after birth until puberty and thereafter undergoes progressive atrophy. It normally maintains most of the radiographic characteristics of the normal thymus. Massive thymic hyperplasia, a rare variant of true thymic hyperplasia is extremely rare during the first two decades of life and clinically can cause mediastinal compression or acute and recurrent pulmonary infection. Two such cases are reported and the clinico-pathology is briefly described and discussed.

The management of severe malaria in children: a review

We have attempted to summarise an approach to management of severe malaria from our experience and that of others from published data in this review. This represents our current state of knowledge and practices which may change as research continues in this field. It also represents what we feel should be the minimum aim in treating severe malaria even at district hospital level. It focuses on practical issues encountered when admitting such patients: initial assessment, immediate supportive management, use of transfusion, appropriate anti-malarial treatment and ongoing management.

Pattern of acute rheumatic fever in a local teaching hospital

Hospital records of children admitted to the department of Paediatrics, University Hospital, Kuala Lumpur, from January 1981 to December 1990, who were diagnosed to have acute rheumatic fever (ARF) were studied. 134 children satisfied the Jones' modified criteria, thus giving a hospital incidence of 21.2/100,000 paediatric admission per year, of which incidence of first attack was 15.8/100,000 per year and recurrent attack was 5.38/100,000 per year. The M:F ratio is 1.39:1. Majority of cases occur in the 6-11 years age group with 6 cases encountered below the age of 5. The Indians had a higher relative risk to develop both the first acute attack as well as recurrences with a relative risk of 2.4 and 4.10 respectively as compared to the Malays. Majority of the patients, irrespective of the ethnic group, came from families with low income.

Ocular leukemia in King Abdulaziz University Hospital - Jeddah

To the best of our knowledge, ocular leukemia has not been reported in Saudi Arabia. Seventy-two leukemia patients were seen in King Abdulaziz University Hospital in Jeddah over the last 10 years. Thirty-one of those patients had an ocular examination. Seventeen of these were found to have ocular abnormalities related to leukemia. Ten had acute lymphoblastic leukemia, four had acute myeloid leukemia and three had chronic myeloid leukemia. The retina and vitreous were involved in 12 of the ocular relapses, the anterior segment leukemic infiltrate in nine, glaucoma in five, opportunistic infection in four, cranial nerve palsies in three, proptosis and hypotony in two. Conjunctival hemorrhage, choroidal infiltrate and cataract were present in one relapse each. The optic nerve was involved in nine relapses, which is a serious condition that requires immediate intervention to save the patient's sight. Computed tomography (CT) scan of the brain and orbit was useful in differentiating between optic nerve infiltrate and papilledema. Most ocular relapses responded well to chemotherapy except relapses with optic nerve and anterior segment infiltrate, which required irradiation to save the patient's sight and prevent further relapses. In conclusion, the presented data have shown that ocular leukemia is not rare and emphasizes the importance of early ophthalmologic examination and radiation.

Absenteeism in the workforce, Klang Valley, Malaysia--preliminary report

The aim of this study was to determine the prevalence of sickness absenteeism among the three types of agencies, government, semi-government (boards) and private (public) companies. The methodology involved eliciting retrospective data on medical leave over the year 1990 by requesting the agencies to fill up a questionnaire (Appendix I), and calculating the indices of absenteeism from this data. The results show that the private agencies scored higher for all the indices but only the "lost time" percentage was significantly increased. Females also had significantly higher severity of sickness absenteeism rates in all the agencies. Overtime work was associated with higher absenteeism indices, markedly noted in the private agencies. In conclusion, agencies showed work out their own indices of absenteeism so that it could be compared with national rates.

The usefulness of a stretch-polyester pouch to encase implanted pacemakers and defibrillators

This study was undertaken to assess the effects of enclosing permanent pacemaker and ICD pulse generators in a stretch-polyester pouch prior to implantation. Follow-up of 223 patients with oversized pacemakers and with ICDs and 344 with standard-sized pacemaker pulse generators showed that the pouch was effective in decreasing the frequency of pulse generator migration and extrusion.

Multiplane transesophageal echocardiography: our initial experience

We present our experience in the diagnostic assessment of a wide spectrum of cardiovascular disorders using multiplane transesophageal echocardiography (MP-TEE). Two hundred and seventeen patients in the age range of 11-71 years were subjected to MP-TEE from January to November 1993. The male:female ratio was 1.1:1. One hundred and ten patients had predominantly mitral valve disease of rheumatic origin, eleven had mitral valve prolapse, twenty patients had aortic valve disease and thirty seven patients had more than one valve involvement. Six patients with suspected prosthetic heart valve dysfunction and ten patients of hypertrophic cardiomyopathy were also studied. Two patients had unexplained pulmonary hypertension, three had pericardial disease and three had proximal aortic dissections. Twenty six patients with congenital heart disease were studied of which nineteen had atrial septal defects, one had corrected transposition of great vessels with pulmonic stenosis and one adult had Ebstein's anomaly of the tricuspid valve. In our experience, MP-TEE enhances the versatility of TEE by providing incremental diagnostic information and enhancing delineation of pathology. The procedure was well-tolerated and no complications occurred.

Partitioning and inactivation of viruses during isolation of albumin and immunoglobulins by cold ethanol fractionation

Albumin solutions invariably transmitted infectious hepatitis viruses before the introduction of pasteurisation in the final container. Immunoglobulin solutions (the older intramuscular as well as the current intravenous ones), on the other hand, only rarely transmitted hepatitis. The apparent safety of the latter was usually attributed to the presence of neutralizing antibodies and to the fractionation process. It was shown that viruses tend to concentrate in those fractions of the cold ethanol precipitation procedure which are used neither for albumin nor for immunoglobulin preparations. Additionally, ethanol alone inactivates some viruses, albeit much less at low temperatures than at room temperature. According to EC-directives, all manufacturers of stable blood products must introduce production steps which inactivate viruses or they have to prove that certain production steps, which are already being used, do inactivate viruses. In either case, the inactivation has to be validated with appropriate experiments. Procedures that are now recognized as virucidal are, e.g., pasteurisation (i.e., heating of the liquid product at 60 degrees C for 10 hours), solvent/detergent (S/D) treatment, photodynamic treatment, or incubation at pH4 with pepsin.

Fishy-looking liars: deception judgment from expectancy violation

To explain how people judge that others are lying, an expectancy-violation model is proposed. According to the model, deception is perceived from nonverbal behavior that violates normative expectation. To test the model, 3 experiments were conducted, 2 in the United States and 1 in India. In each experiment, people described acquaintances while exhibiting weird nonverbal behaviors, such as arm raising, head tilting, and staring. Other Ss watched the videotapes of the descriptions and made deception judgments. Consistent with the expectancy-violation model, both American undergraduates and Indian illiterates inferred deception from weird behaviors. Implications of the model are discussed.

Leukemic infiltrate versus anterior uveitis

Anterior segment leukemic infiltrate (ASLI) is rare; it is found in 0.5% to 2.5% of all leukemic relapses. Its clinical manifestations, at times, are similar to those of anterior uveitis (AU). We report the cases of three patients, all of whom had ASLI as their primary manifestation of relapse. We observed some major clinical differences between ASLI and AU that may help differentiate these two conditions without using anterior chamber paracentesis and/or iris biopsy. The development of resistance to leukemic therapy is the major factor in treatment failure.

Fishy-looking liars: Deception judgment from expectancy violation

To explain how people judge that others are lying, an expectancy-violation model is proposed. According to the model, deception is perceived from nonverbal behavior that violates normative expectation. To test the model, 3 experiments were conducted, 2 in the United States and 1 in India. In each experiment, people described acquaintances while exhibiting weird nonverbal behaviors, such as arm raising, head tilting, and staring. Other Ss watched the videotapes of the descriptions and made deception judgments. Consistent with the expectancy-violation model, both American undergraduates and Indian illiterates inferred deception from weird behaviors. Implications of the model are discussed.

Semliki Forest virus envelope proteins function as proton channels

It has been shown that isolated nucleocapsids of Semliki Forest virus (SFV) contract upon low pH exposure (Soederlund et al., 1972). This contraction of the nucleocapsids has been used as an indicator to demonstrate that the spike proteins of SFV can translocate protons into the interior of the virus particle upon low pH (5.8) exposure. Spikeless virus particles obtained after bromelain digestion, which were used as a control, did not translocate protons. This implies that the ectodomain of the spike plays a crucial role for the proton translocation.

Diagnosis and management of purulent pericarditis. Experience with pericardiectomy

Twelve cases of purulent pericarditis seen over 6 years are described. Staphylococcus aureus was the most common causative organism (six patients), and a respiratory infection was the most common preceding illness. The chest radiograph and echocardiogram were useful pointers to the diagnosis, but the electrocardiogram was not reliable. Antibiotics, surgical drainage, and pericardiectomy were used in all 12 cases. There was one death (8.3%), which occurred in a patient who was seen late. A review of the literature dealing with the diagnosis and management of this condition is presented. The importance of early diagnosis before a significant degree of cardiac tamponade occurs is noted. Although there is general agreement that surgical drainage is mandatory, the approach, methods of drainage, and extent of pericardial resection have been the subject of some discussion, and at least seven techniques are available. We conclude that pericardiectomy has a definite place in the management of purulent pericarditis.

Semliki Forest virus induced cell-cell fusion at neutral extracellular pH

Semliki Forest virus-induced cell-cell fusion from within was considered to exclusively occur at mildly acidic pH (less than 6.2). Data of this study show that such cell fusion can also be triggered by transient acidification of the cytoplasm of infected cells at an extracellular, neutral pH. Results were obtained by utilizing NH4Cl pulses combined with covalent modification of cell surface proteins. The observation implies a revision of the current consensus regarding the mechanism of Semliki Forest virus induced cell-cell fusion. We propose a model in which at least two peptide segments of the viral spike protein E1 may be involved in triggering the fusion event.

The use of sulfite to study the mechanism of membrane fusion induced by E1 of Semliki Forest virus

In this study we have used 35S-labeled sulfite to modify the disulfide bonds of the proteins at the cell surface of Semliki Forest-infected Aedes albopictus cells before and after low pH treatment. This reagent specifically cleaves disulfide bonds and concomitantly reacts with the newly formed cysteines, thereby labeling the respective protein. Treatment of the infected cells with sulfite led to inhibition of the fusion activity only when applied after low pH exposure. These cells exhibited substantial incorporation of the label into the viral E1 glycoprotein as compared to the E2 glycoprotein. These results provide direct evidence for the low pH-induced conformational change of E1 during the generation of its fusogenic potential.

Semliki Forest virus particles containing only the E1 envelope glycoprotein are infectious and can induce cell-cell fusion

Hydrophobic interaction chromatography (phenyl- and octyl-Sepharose) was performed with Semliki Forest virus to investigate the effect of low pH on its hydrophobicity. At neutral pH, the virus could be bound to the column and completely eluted by the detergent NP-40. Low pH treatment of virus prior to application to the column resulted in stronger binding as reflected by the increased amount of detergent necessary to totally elute the virus. If, however, the low pH treatment was done after binding of the virus to the column, only 15% of the input virus could be eluted by the detergent, indicating a drastic increase in hydrophobicity. Thus binding of the virus to a hydrophobic environment potentiates the effect of low pH on viral hydrophobicity. Trypsin digestion of column-bound virus after low pH treatment resulted in complete digestion of E2 and E3; however, E1 was totally resistant. From this result, we conclude that E1 alone is responsible for the hydrophobic interaction. We have made use of these observations to produce viral particles which were devoid of E2 and E3 by trypsin digestion in the presence of octyl glucoside. These E1 viral particles were infectious and could induce membrane fusion. We conclude that only E1 is necessary and sufficient to mediate membrane fusion. Acid pH induces a drastic increase in the hydrophobicity of E1 which probably facilitates its interaction with the lipid bilayers during the fusion event in endosomes.

Fusion of Semliki Forest virus infected Aedes albopictus cells at low pH is a fusion from within

Herein, it is shown for the first time that the mechanism of fusion followed in Aedes albopictus cells infected with Semliki Forest virus induced by low pH exposure is a "fusion from within". Several parameters were studied disclosing that the development of the fusion capacity of the cells is directly related to the synthesis of viral specific products. These findings were further substantiated by utilizing various chemicals to inhibit viral specific events during infection, protein synthesis and maturation. Removal of exogenous virions produced at 16 hours post infection by proteinase K digestion clearly revealed that the viral proteins located at the cell surface and not the exogenous virions were responsible for the fusogenic activity. The presence of these viral proteins at the cell surface was disclosed by immunofluorescence employing anti-SFV antibodies elicited in rabbits. Additional evidence for the participation of the viral proteins at the cell surface in the fusion reaction was obtained by Bromelaine digestion which inhibited the fusion and tunicamycin treatment which only partially inhibited the fusion but revealed the inevitable presence of the E1 protein.

One-step separation of the components of Semliki Forest virus by cation exchange chromatography

Although several procedures for isolating viral proteins have been described, the simultaneous separation of all the viral macromolecules in a single step has not yet been reported. We now describe TUA (Triton X-100, urea, acetic acid, pH 4.2)-SP (Sulphopropyl)-Trisacryl cation exchange chromatography, which proved to be ideal for this purpose. Optimal conditions for chromatography were established by screening on TUA-PAGE (polyacrylamide gel electrophoresis) using a horizontal linear 0-8.5 M urea gradient followed by identification of the proteins by SDS-PAGE in the second dimension. Segregation of the constituents of Semliki Forest virus cultivated in two cell lines (chicken embryo fibroblasts and Aedes albopictus cells) was studied, considering that the proteins have identical primary sequences but diverse post-translational modifications, thereby allowing the efficacy of the procedure and its applicability to different viruses to be tested. The results show that the RNA and lipids did not bind to the cation exchange in TUA and were eluted in the flow-through fractions. The proteins were fractionated using 3 linear NaCl gradients in TUA. SDS-PAGE revealed that all the proteins could be purified by this procedure. Furthermore, a direct correlation was obtained between the distance migrated by the proteins in the TUA-PAGE and their order of elution from the TUA-cation exchange column.

Conformational changes at pH 6 on the cell surface of Semliki Forest virus-infected Aedes albopictus cells

The mechanism of Semliki Forest virus-induced fusion from within at low pH was studied in Aedes albopictus cells. The fusion was found to occur in at least two steps, namely, a fast initial step which is pH dependent and temperature independent, and a second slower process which is pH independent and temperature dependent. The initiation step induced by low pH exposure constitutes an irreversible conformational change of a protein probably of viral origin located at the cell surface.

Quantitation of digital clubbing by shadowgram technique

Finger clubbing was quantified from the magnified silhouette of the right index finger in controls and patients with clubbing, using a simple shadowgram technique. There was good correlation between clinical assessment and measurement of both the profile angle and the hyponychial angle. The hyponychial angle appeared to be a more accurate indicator of clubbing than the profile angle.

Acute leukemia in Malaysian children

A review of acute childhood leukemia in the University Hospital, Kuala Lumpur reveals no significant differences in either the epidemiological or clinical features between Malaysian and Caucasian children. BCG does not appear to have conferred any protection against the occurrence of leukemia. With the introduction of total therapy 4 of 10 patients with good prognostic features and 3 of 15 patients with poor prognostic features have survived 3 years. Prognosis appears to correlate with adopted clinical criteria.

Induction of multinucleate cells by 8-MOP and UV treatment in vitro and in vivo

Fibroblast cells were treated with a single dose of 8-methoxypsoralen (8-MOP) and long-wave UV irradiation in vitro and the cytotoxic effects of the treatment followed up for 5 passages. During the first passage, there was an inhibition in cell proliferation, the induction of chromosomal aberrations and the production of macrocells as well as cells with more than one nucleus. In the subsequent passages, the proliferation rate of the cells gradually normalized but there was a concomitant increase in chromosomal aberrations and in the number of macrocells and multinucleate cells. Specimens, which were taken from the uninvolved skin of psoriatic patients who had been treated between 20 and 40 times with an oral dose of 8-MOP and black light irradiation (PUVA) also revealed the presence of binucleate, tetranucleate and multinucleate epidermal cells as well as binucleate and tetranucleate dermal fibroblasts.

Photo-onycholysis induced by 8-methoxypsoralen

Two patients, who we had under surveillance since 1969, were found to develop photo-onycholysis from orally administered 8-methoxypsoralen and sunlight irradiation. Morphological examination of the nail bed revealed characteristics of a microtrauma. The photosensitizing effect of the drug induced the generation numerous binucleate, tetranucleate and multinucleate epithelial cells as well as numerous binucleate and tetranucleate fibroblasts in the dermis.

An analysis of pancreatic enzymes used in epidermal separation

A comparative enzyme analysis was performed on 3 pancreatic extracts generally used for dermal-epidermal separation, namely, crude trypsin (Difco), crude trypsin (Sigma) and pancreatin. A fourth pancreatic extract, crude lipase, was subjected to a corresponding analysis. The 4 extracts were assayed for activities of: protease (total), trypsin, chymotrypsin, carboxypeptidase-A, amylase, elastase, lipase, esterase, arylesterase and ribonuclease. Relative activities of the different proteolytic enzymes were individualized by utilizing specific inhibitors. Insignificant differences were observed between the enzyme activities of crude trypsin (Difco) and pancreatin. Crude lipase displayed similar enzyme activities as these two extracts in addition to high lipolytic, esterolytic and arylesterolytic activities. Crude trypsin (Sigma) exhibited higher tryptic and chymotryptic activities than the other extracts but lacked all further enzyme activities. Epidermal separation was performed using similar incubation conditions for each extract and skin from the same donor. Ultrastructural examination of the detached epidermis revealed that a more effective separation could be achieved by crude lipase.

Mode of dermal-epidermal adhesion

The mode of dermal-epidermal adhesion was investigated by a systematic enzyme digestion of the dermo-epidermal junction. The anchoring fibrils and filaments were found to consist of elastin and collagen-like filaments which intertwine to form the adepidermal membrane. A model on the possible in situ conditions is proposed.