Recommendations on prevention and screening for colorectal cancer in Hong Kong

Colorectal cancer is the commonest cancer in Hong Kong. The Cancer Expert Working Group on Cancer Prevention and Screening was established in 2002 under the Cancer Coordinating Committee to review local and international scientific evidence, assess and formulate local recommendations on cancer prevention and screening. At present, the Cancer Expert Working Group recommends that average-risk individuals aged 50 to 75 years and without significant family history consult their doctors to consider screening by: (1) annual or biennial faecal occult blood test, (2) sigmoidoscopy every 5 years, or (3) colonoscopy every 10 years. Increased-risk individuals with significant family history such as those with a first-degree relative diagnosed with colorectal cancer at age ≤60 years; those who have more than one first-degree relative diagnosed with colorectal cancer irrespective of age at diagnosis; or carriers of genetic mutations associated with familial adenomatous polyposis or Lynch syndrome should start colonoscopy screening earlier in life and repeat it at shorter intervals.

Reconstruction of Chronic Subtalar Dislocation

Introduction

Subtalar dislocations are a rare injury, comprising 1–2% of all large joint dislocations and 15% of all peri-talar injuries. Most subtalar dislocations are managed acutely, with the documented reconstruction of chronic dislocations rare. This case report aims to present our experience with the first documented use of an Ilizarov frame for bony and soft tissue reconstruction in a case of chronic subtalar dislocation.

Materials and methods

A single patient surgically treated for chronic subtalar dislocation was followed over a 2-year period, and retrospectively reviewed.

Results

A 67-year-old lady presented with an over 10-year history of worsening ankle pain and significant varus deformity with skin contractures, limiting ambulation over the past 6 months. Computed tomography confirmed medial dislocations of the subtalar and talonavicular joints with head and neck fractures of the talus and generalized osteoarthritis. A two-stage reconstruction involving an Ilizarov frame and subsequent arthrodesis allowed for correction of soft tissue and bone with the return of independent ambulation.

Conclusion

Although the correction of bony deformities is important in reconstruction, soft tissue management is crucial and must not be overlooked. An Ilizarov frame is ideal for correction of both the bony deformity and soft tissue contractures. Arthrodesis can be performed when the overlying soft tissue is able to accommodate correction of the varus deformity and reduction of the dislocations. While an Ilizarov frame requires both an experienced surgeon and a motivated patient, in the right hands, good functional recovery can be returned.

How to cite this article

Chan MC, Khan SA, Tan JGM. Reconstruction of Chronic Subtalar Dislocation. Strategies Trauma Limb Reconstr 2019;14(1):53–56.

Recommendations on prevention and screening for breast cancer in Hong Kong

In Hong Kong, breast cancer is the most common cancer among women and poses a significant health care burden. The Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) was set up in 2002 by the Cancer Coordinating Committee to review and assess local and international scientific evidence, and to formulate recommendations for cancer prevention and screening. After considering the local epidemiology, emerging scientific evidence, and local and overseas screening practices, the CEWG concluded that it was unclear whether population-based breast cancer screening did more harm than good in local asymptomatic women at average risk. The CEWG considers that there is insufficient evidence to recommend for or against population-based mammography screening for such individuals. Women who consider breast cancer screening should be adequately informed about the benefits and harms. The CEWG recommends that all women adopt primary preventive measures, be breast aware, and seek timely medical attention for suspicious symptoms. For women at high risk of breast cancer, such as carriers of confirmed BRCA1/2 deleterious mutations and those with a family history of breast cancer, the CEWG recommends that they seek doctor's advice for annual mammography screening and the age at which the process should commence. Additional annual screening by magnetic resonance imaging is recommended for confirmed BRCA1/2 mutation carriers or women who have undergone radiation therapy to the chest between the age of 10 and 30 years. Women at moderate risk of breast cancer should discuss with doctors the pros and cons of breast cancer screening before making an informed decision about mammography screening every 2 to 3 years.

Optimising the utility of pleural fluid adenosine deaminase for the diagnosis of adult tuberculous pleural effusion in Hong Kong

INTRODUCTION

Pleural fluid adenosine deaminase level can be applied to rapidly detect tuberculous pleural effusion. We aimed to establish a local diagnostic cut-off value for pleural fluid adenosine deaminase to identify patients with tuberculous pleural effusion, and optimise its utility.

METHODS

We retrospectively reviewed the medical records of consecutive adults with pleural fluid adenosine deaminase level measured by the Diazyme commercial kit (Diazyme Laboratories, San Diego [CA], United States) during 1 January to 31 December 2011 in a cluster of public hospitals in Hong Kong. We considered its level alongside early (within 2 weeks) findings in pleural fluid and pleural biopsy, with and without applying Light's criteria in multiple scenarios. For each scenario, we used the receiver operating characteristic curve to identify a diagnostic cut-off value for pleural fluid adenosine deaminase, and estimated its positive and negative predictive values.

RESULTS

A total of 860 medical records were reviewed. Pleural effusion was caused by congestive heart failure, chronic renal failure, or hypoalbuminaemia caused by liver or kidney diseases in 246 (28.6%) patients, malignancy in 198 (23.0%), non-tuberculous infection in 168 (19.5%), tuberculous pleural effusion in 157 (18.3%), and miscellaneous causes in 91 (10.6%). All those with tuberculous pleural effusion had a pleural fluid adenosine deaminase level of ≤100 U/L. When analysis was restricted to 689 patients with pleural fluid adenosine deaminase level of ≤100 U/L and early negative findings for malignancy and non-tuberculous infection in pleural fluid, the positive predictive value was significantly increased and the negative predictive value non-significantly reduced. Using this approach, neither additionally restricting analysis to exudates by Light's criteria nor adding closed pleural biopsy would further enhance predictive values. As such, the diagnostic cut-off value for pleural fluid adenosine deaminase is 26.5 U/L, with a sensitivity of 87.3%, specificity of 93.2%, positive predictive value of 79.2%, negative predictive value of 96.1%, and accuracy of 91.9%. Sex, age, and co-morbidity did not significantly affect prediction of tuberculous pleural effusion using the cut-off value.

CONCLUSION

We have established a diagnostic cut-off level for pleural fluid adenosine deaminase in the diagnosis of tuberculous pleural effusion by restricting analysis to a level of ≤100 U/L, and considering early pleural fluid findings for malignancy and non-tuberculous infection, but not Light's criteria.

Betti reaction enables efficient synthesis of 8-hydroxyquinoline inhibitors of 2-oxoglutarate oxygenases

There is interest in developing potent, selective, and cell-permeable inhibitors of human ferrous iron and 2-oxoglutarate (2OG) oxygenases for use in functional and target validation studies. The 3-component Betti reaction enables efficient one-step C-7 functionalisation of modified 8-hydroxyquinolines (8HQs) to produce cell-active inhibitors of KDM4 histone demethylases and other 2OG oxygenases; the work exemplifies how a template-based metallo-enzyme inhibitor approach can be used to give biologically active compounds.

Emergence of a novel GII.17 norovirus – End of the GII.4 era?

In the winter of 2014/15 a novel GII.P17-GII.17 norovirus strain (GII.17 Kawasaki 2014) emerged, as a major cause of gastroenteritis outbreaks in China and Japan. Since their emergence these novel GII.P17-GII.17 viruses have replaced the previously dominant GII.4 genotype Sydney 2012 variant in some areas in Asia but were only detected in a limited number of cases on other continents. This perspective provides an overview of the available information on GII.17 viruses in order to gain insight in the viral and host characteristics of this norovirus genotype. We further discuss the emergence of this novel GII.P17-GII.17 norovirus in context of current knowledge on the epidemiology of noroviruses. It remains to be seen if the currently dominant norovirus strain GII.4 Sydney 2012 will be replaced in other parts of the world. Nevertheless, the public health community and surveillance systems need to be prepared in case of a potential increase of norovirus activity in the next seasons caused by this novel GII.P17-GII.17 norovirus.

Nasal CPAP reduces systemic blood pressure in patients with obstructive sleep apnoea and mild sleepiness

BACKGROUND

A randomised controlled study was undertaken to examine the effect of nasal continuous positive airway pressure (CPAP) on 24 hour systemic blood pressure (BP) in patients with obstructive sleep apnoea (OSA).

METHODS

Patients were fitted with an ambulatory BP measuring device as outpatients during normal activities and recorded for 24 hours before starting therapeutic or subtherapeutic (4 cm H(2)O) CPAP treatment. BP monitoring was repeated before completion of 12 weeks of treatment. The primary end point was the change in 24 hour mean BP.

RESULTS

Twenty three of 28 participants in each treatment arm completed the study. There was no significant difference between the two groups in age, body mass index, Epworth Sleepiness Score, apnoea-hypopnoea index, arousal index, and minimum Sao(2). Twenty four patients were hypertensive. The pressure in the therapeutic CPAP group was 10.7 (0.4) cm H(2)O. CPAP usage was 5.1 (0.4) and 2.6 (0.4) hours/night for the therapeutic and subtherapeutic CPAP groups, respectively (p<0.001). After 12 weeks of treatment there were significant differences between the two CPAP groups in mean (SE) changes in 24 hour diastolic BP (-2.4 (1.2) v 1.1 (1.0) mm Hg (95% CI -6.6 to -0.5), p = 0.025); 24 hour mean BP (-2.5 (1.3) v 1.3 (1.1) mm Hg (95% CI -7.2 to -0.2), p = 0.037); sleep time systolic BP (-4.1 (2.1) v 2.2 (1.8) mm Hg (95% CI -11.8 to -0.7), p = 0.028); and sleep time mean BP (-3.6 (1.7) v 1.3 (1.4) mm Hg (95% CI -9.2 to -0.4), p = 0.033).

CONCLUSIONS

Compared with subtherapeutic CPAP, 12 weeks of treatment with therapeutic CPAP leads to reductions in 24 hour mean and diastolic BP by 3.8 mm Hg and 3.5 mm Hg, respectively, in mildly sleepy patients with OSA.

Radiology curriculum for medical students: Clinicians' perspectives

This study was conducted to establish clinicians' perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty-six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost-effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups.

Impact of severe acute respiratory syndrome (SARS) on pulmonary function, functional capacity and quality of life in a cohort of survivors

OBJECTIVE

To examine the impact of severe acute respiratory syndrome (SARS) on pulmonary function, exercise capacity, and health-related quality of life (HRQoL) among survivors.

METHODS

110 survivors with confirmed SARS were evaluated at the Prince of Wales Hospital, HK at the end of 3 and 6 months after symptom onset. The assessment included lung volumes (TLC, VC, RV, FRC), spirometry (FVC, FEV1), carbon monoxide transfer factor (TLCO adjusted for haemoglobin), inspiratory and expiratory respiratory muscle strength (Pimax and Pemax), 6 minute walk distance (6MWD), chest radiographs, and HRQoL by SF-36 questionnaire.

RESULTS

There were 44 men and 66 women with a mean (SD) age of 35.6 (9.8) years and body mass index of 23.1 (4.8) kg/m2. Seventy (64%) were healthcare workers. At 6 months 33 subjects (30%) had abnormal chest radiographs; four (3.6%), eight (7.4%), and 17 (15.5%) patients had FVC, TLC, and TLCO below 80% of predicted values; and 15 (13.9%) and 24 (22.2%) had Pimax and Pemax values below 80 cm H2O, respectively. The 6MWD increased from a mean (SD) of 464 (83) m at 3 months to 502 (95) m (95% CI 22 to 54 m, p<0.001), but the results were lower than normal controls in the same age groups. There was impairment of HRQoL at 6 months. Patients who required ICU admission (n = 31) had significantly lower FVC, TLC, and TLCO than those who did not.

CONCLUSION

The exercise capacity and health status of SARS survivors was considerably lower than that of a normal population at 6 months. Significant impairment in surface area for gas exchange was noted in 15.5% of survivors. The functional disability appears out of proportion to the degree of lung function impairment and may be related to additional factors such as muscle deconditioning and steroid myopathy.

Palladium(II) and platinum(II) analogues of luminescent diimine Triangulo complexes supported by triply bridging sulfide ligands: structural and spectroscopic comparisons

Reaction of [M(L-L)Cl(2)] [M = Pd, Pt; L-L = 4,4'-di-tert-butyl-2,2'-bipyridine ((t)Bu(2)bpy), 4,4'-dimethylcarboxylate-2,2'-bipyridine ((CO(2)Me)(2)bpy), bis(diphenylphosphino)methane (dppm)] with Na(2)S in refluxing methanol afforded [M(3)((t)Bu(2)bpy)(3)(mu(3)-S)(2)](2+) [M = Pd (1a), Pt (2a)], [M(3)((CO(2)Me)(2)bpy)(3)(mu(3)-S)(2)](2+) [M = Pd (1b), Pt (2b)], and [Pt(3)(dppm)(3)(mu(3)-S)(2)](2+) (3) as perchlorate salts. X-ray crystal analysis revealed that 1a, 1b, 2a, and 3 have triangular M(3)S(2) core structures. The three metal atoms in 1a, 2a, and 3 form virtual equilateral triangles with intramolecular Pd-Pd and Pt-Pt separations of 3.027(1)-3.065(1) and 3.104(1)-3.154(1) A, respectively. An isosceles triangle of Pd(3) atoms is observed in the molecular structure of 1b. The (1)MLCT absorption of 2a and 2b appears at 415 and 448 nm, respectively, in dichloromethane and is significantly red-shifted from the lowest energy absorption band of the Pd(3) analogues. Complex 1a exhibits weak photoluminescence in the solid state at 77 and 298 K (uncorrected lambda(max) 760 and 730 nm, respectively) while the 77 K solid-state emission of 1b (uncorrected lambda(max) 760 nm) is also weak. At 77 K, complexes 2a, 2b, and 3 display broad unstructured emissions at lambda(max) 616-630 nm in the solid state. Ligand-field excited states are tentatively assigned for these emissions.

Organic light-emitting materials based on bis(arylacetylide)platinum(II) complexes bearing substituted bipyridine and phenanthroline ligands: photo- and electroluminescence from 3MLCT excited states

We present the synthesis and photophysical and electroluminescent properties for a series of platinum(II) alpha-diimine bis(arylacetylide) complexes. The molecular structures of five derivatives have been elucidated by X-ray crystallography. Intermolecular pi-pi interactions (between aromatic diimine and phenylacetylide moieties) are apparent in the crystal lattices of two of these. All bis(phenylacetylide) derivatives exhibit intense triplet metal-to-ligand charge transfer (MLCT) photoluminescence in the solid state and in fluid solutions at room temperature. The impact of different solvents, substituents on the diimine ligands, and complex concentrations upon their emissive behavior have been examined and demonstrates that their emission energies can be systematically modified. Application of the 3MLCT excited state of the [Pt(alpha-diimine) (C(triple bond)CPh)2] materials in single- and double-layer organic light-emitting devices are described. The bis(butadiynyl) complex [Pt(4,4'-dtbpy)(C(triple bond)C-C(triple bond)CPh)2] (dtbpy = 4,4'-di-tert-butyl-2,2'-bipyridine) displays strong solid-state and solution phosphorescence at 77 and 298 K; the associated excited state is proposed to arise from both acetylenic 3pi pi*(C(triple bond)C-C(triple bond)CPh) and 3MLCT [Pt --> pi*(diimine)] transitions.

Severe tricuspid regurgitation after heart transplantation

BACKGROUND

Tricuspid regurgitation (TR) is common after heart transplantation. However, the incidence of severe TR and the incidence of symptoms after echocardiographic diagnosis of severe TR have not been documented. The purpose of this study is to determine the incidence of severe TR and its clinical significance in the heart transplant population.

METHODS

We reviewed echocardiograms (echo) of all heart transplant patients coming for regular echocardiographic follow-up between 1990 and 1995. We reviewed the charts of all patients who had echo diagnosis of severe TR.

RESULTS

A total of 336 patients had echo follow-up during this time period. The number of months post-heart transplant to last echo was 54 +/- 50 (range, 1 to 265 months). Ninety patients had moderate TR and 23 patients had severe TR. Mean time from heart transplantation to diagnosis of severe TR was 43 +/- 38 months (range, 1 to 132). Using Cutler-Ederer analysis, at 5 years, 92.2% of surviving patients were free from severe TR. At 10 years, 85.8% of surviving patients were free from severe TR. Of the 23 patients with severe TR, 17 had charts available for review. The mean number of prior endomyocardial biopsies was 28 +/- 21 (range, 3 to 88). These patients were followed for 35 +/- 18 months after diagnosis. During this period, they developed significant heart failure and peripheral edema. Six patients eventually underwent tricuspid valve replacement.

CONCLUSIONS

Moderate to severe TR commonly occurs following heart transplantation. Severe TR is associated with significant morbidity.

Identification and regulation of receptor tyrosine kinases Rse and Mer and their ligand Gas6 in testicular somatic cells

Receptor tyrosine kinases act to convey extracellular signals to intracellular signaling pathways and ultimately control cell proliferation and differentiation. Rse, Axl, and Mer belong to a newly identified family of cell adhesion molecule-related receptor tyrosine kinase. They bind the vitamin K-dependent protein growth arrest-specific gene 6 (Gas6), which is also structurally related to the anticoagulation factor Protein S. The aim of this study is to investigate the possible role of Rse/Axl/Mer tyrosine kinase receptors and their ligand in regulating testicular functions. Gene expression of Rse, Axl, Mer, and Gas6 in the testis was studied by reverse transcriptase-polymerase chain reaction (RT-PCR) and Northern blot analysis. The results indicated that receptors Rse and Mer and the ligand Gas6 were expressed in the rat endothelial cell line (TR1), mouse Leydig cell line (TM3), rat peritubular myoid cell line (TRM), mouse Sertoli cell line (TM4), and primary rat Sertoli cells. Axl was not expressed in the testicular somatic cells by RT-PCR or Northern blot analysis. The highest level of expression of Gas6 messenger RNA (mRNA) was observed in the Sertoli cells, and its expression was responsive to the addition of forskolin in vitro. The effects of serum, insulin, and transferrin on Gas6 expression by TM4 cells were examined. It was shown that they all exhibited an up-regulating effect on Gas6 expression. The forskolin-stimulated Gas6 expression was accompanied by an increase in tyrosine phosphorylation of the Rse receptor in vitro, suggesting that Gas6 may exhibit an autocrine effect in the Sertoli cells through multiple tyrosine kinase receptors. Our studies so far have demonstrated that tyrosine kinase receptors Rse and Mer and their ligand Gas6 are widely expressed in the testicular somatic cell lines and may play a marked role in promoting testicular cell survival.

Luminescent mononuclear and binuclear cyclometalated palladium(II) complexes of 6-phenyl-2,2 bipyridines: spectroscopic and structural comparisons with platinum(II) analogues

The mononuclear cyclometalated Pd(II) complexes [Pd(L1)X] (HL1 = 6-phenyl-2,2'-bipyridine; X = Cl, la; Br, 1b; I, 1c), [Pd(L1)PPh3]+ (1d), [Pd(L2-5)Cl] [2a-5a, HL2-5 = 4-(aryl)-6-phenyl-2,2'-bipyridine; aryl = phenyl (2), 4-chlorophenyl (3), 4-tolyl (4), 4-methoxyphenyl (5)] and the binuclear derivatives [Pd2(L1-5)2(mu-dppm)]2+ (1e-5e, dppm = bis(diphenylphosphino)methane) and [Pd2(L1)2(mu-dppCs)]2+, (1f, dppC5 = 1,5-bis(diphenylphosphino)pentane) were prepared. The crystal structures of 1d(ClO4), 1e(ClO4)2 x DMF, and 2e(ClO4)2 have been determined by X-ray crystallography. The magnitude of the Pd-Pd distances in le and 2e (3.230(1) and 3.320(2) A, respectively) suggest minimal metal-metal interaction, although pi-stacking of the aromatic ligands (interplanar separations 3.34 and 3.35 A, respectively) is evident. All complexes display low-energy UV absorptions at lambda approximately 390 nm, which are tentatively assigned to 1MLCT transitions; red shifts resulting from Pd-Pd interactions in the binuclear species are not apparent. The complexes in this work are non-emissive at 298 K, but the cationic derivatives exhibit intense luminescence at 77 K. The structured emissions of 1d and 1f in MeOH/EtOH glass (lambdamax 467-586 nm) and all cationic species in the solid state (lambdamax 493-578 nm) are assigned to intraligand excited states. Complexes le-5e display dual emissions in MeOH/EtOH glass at 77 K, and the broad structureless bands at lambdamax 626-658 nm are attributed to pi-pi excimeric IL transitions. A comparison between the photophysical properties of Pd(II) and Pt(II) congeners is presented.

Use of physical restraints on elderly patients: an exploratory study of the perceptions of nurses in Hong Kong

A qualitative study was designed to explore nurses' perceptions of the use of physical restraints on elderly patients in Hong Kong. Content analysis of semi-structured interviews with 20 registered nurses working in medical and geriatric settings of two regional hospitals revealed that although nurses generally had mixed feelings about the use of physical restraints on elderly patients, they did not question this 'routine' practice and their knowledge about the consequences and alternatives to the use of restraint was limited. It was found that nurses had an overriding concern in ensuring elderly patients' physical safety and using restraints therefore provided them with a sense of security. The deleterious impact of restraint on the care received by elderly patients was largely unrecognized. Implications for practice and future studies are discussed in the light of these findings.

Effects of diet on measurement of nitric oxide metabolites

1. The present study investigated whether a low nitrate/nitrite diet could minimize variability in the measurement of endogenous plasma and urine nitric oxide (NO) metabolites, nitrate and nitrite (NOx) in normal subjects. 2. Nitrate and nitrite concentrations were measured in plasma and urine as indicators of NO production in six subjects during a free diet and then during a low nitrate/nitrite diet for 6 days. 3. The plasma concentration and 24 h urine NOx/creatinine ratio were significantly lower on the low nitrate/nitrite diet than on the free diet (P < 0.01). Nitric oxide production appeared to vary greatly within and between subjects, but these variations were substantially decreased by the fourth day of a low nitrate/nitrite diet. 4. Human plasma and urine NOx measurements should be determined after a low nitrate/nitrite diet for at least 4 days.

Linear epitopes of sperm whale myoglobin identified by polyclonal antibody screening of random peptide library

Distinct enhancement of antibody-specific clones was apparent during the screening against random peptide libraries with antigen-specific polyclonal antibodies. Several sequence motifs obtained from these screenings were homologous with the primary sequence of myoglobin. Two of these motifs have been confirmed as antigenic determinants by competitive inhibition tests using eight-branched synthetic peptides. One of the peptides has a sequence that corresponds to amino acid residues 42-50, KFDRFKHLK, of the myoglobin sequence. This is a new epitope of myoglobin that is reported for the first time. The epitope is located precisely in the "turn' or "loop' region between helices C and D of the crystal structure of myoglobin. The second antibody binding site has a sequence of DIAAKYKELGYQG, and this is located between residues 141-153, which is the C-terminus of myoglobin. This epitope encompassed two linear epitopes of myoglobin, amino acid residues 145-151 and 147-153, that have been reported earlier based on immunochemical characterisation of cleavage fragments of the protein. These results clearly indicate that epitope mapping using polyclonal antibodies against random peptide libraries can identify new epitopes precisely, as well as confirm epitopes of myoglobin obtained earlier using established methodologies.

Stereotactic fine needle aspiration in the management of mammographic abnormalities detected in breast screening

BACKGROUND

Fine needle aspiration (FNA) is used routinely in the management of palpable breast lumps; with the implementation of the stereotactic technique its use has been extended to the investigation of mammographic abnormalities. The advent of breast screening means that many mammographic abnormalities will be detected; because routine open biopsy is impractical and undesirable, stereotactic fine needle aspiration becomes the method of choice for investigation.

METHOD

Within a 28 month interval, 81 Chinese women underwent stereotactic FNA in Kwong Wah Hospital, Hong Kong.

RESULTS

Fifty-one women (62.9%) had a benign cytology result and no further investigations were required. Inconclusive results were obtained in 18.6% of the aspirates. Open biopsy was required in 16 women (19.8%).

CONCLUSION

Stereotactic FNA is very useful in the exclusion of malignancy and the avoidance of open biopsy in asymptomatic women who have mammographic abnormalities.

Neonatal jaundice, aflatoxins and naphthols: report of a study in Ibadan, Nigeria

This study set out to investigate the prevalence of naphthols and aflatoxins in the sera of babies with neonatal jaundice and their mothers in order to determine whether they contribute to the occurrence of unexplained neonatal jaundice in Ibadan. Blood was obtained from 327 jaundiced neonates and 80 of their mothers, and 60 non-jaundiced controls and seven of their mothers admitted to hospital between April 1989 and April 1991. Blood group, bilirubin concentration, erythrocyte G6PD status, aflatoxin and naphthol concentrations in blood were measured. Altogether, 30.9% of the jaundiced neonates were G6PD-deficient, compared with 13.3% of controls (chi 2 = 6.88; p = 0.009). Aflatoxins were detected in 27.4% of jaundiced neonates, 17% of their mothers, 16.6% of controls and 14.4% of control mothers. Naphthols were detected in 7.2% of jaundiced babies, 6.3% of their mothers, 6.25% of control babies and 14.4% of their mothers. Analysis of the data revealed that either G6PD deficiency or the presence of any serum aflatoxin is a risk factor for neonatal jaundice; odds ratio were 2.97 (95%) confidence intervals (CI): 1.31-6.74) and 2.68 (CI: 1.18-6.10), respectively. This study demonstrates that G6PD deficiency and/or the presence of serum aflatoxins are risk factors for neonatal jaundice in Nigeria. Aflatoxins are an additional risk factor not previously reported.

Unusual site of spontaneous first-rib fracture: case report

Spontaneous fractures of the first rib are uncommon and are usually thought to be associated with a malignant process. However, fatigue fractures of the first rib are being encountered increasingly in association with various physical activities. Typically, the fractures occur at the subclavian groove, but in the 48-year-old woman described in this report the fracture was unexpectedly situated in the posterior portion of the rib and was the result of snow shovelling, which was a new activity for the patient.

Intraoperative whole-lung torsion producing pulmonary venous infarction

Pulmonary venous infarction and whole-lung torsion are both rare, life-threatening complications of thoracic operations. A case of whole-lung torsion with resultant pulmonary venous infarction of the entire lung after a nonpulmonary thoracic operation is reported.

Detection of naphthols and aflatoxins in Nigerian cord blood

Widespread use of napthol-containing compounds and frequent contamination of foods by aflatoxins occurs in Nigeria. Napthols cause haemolysis and aflatoxins are hepatotoxic. A study was carried out to determine the extent of fetal exposure to these compounds and their influence on birthweight. Cord blood samples were collected at delivery from 625 babies and their sera were analysed for aflatoxins and naphthols. Mothers' histories and babies' weights were recorded. Naphthols were detected in 6.9% and aflatoxins in 14.6% of serum samples. No correlation was found between the presence of either compound and birthweight. Reported exposure to naphthalene-containing compounds was not related to detection of serum naphthol. Results show considerable fetal exposure to these potentially toxic compounds in Ibadan, Nigeria.

Placental transfer of tetanus toxoid antibodies in Nigerian mothers

The aim of this study was to assess the efficacy of the tetanus toxoid immunization programme in Nigeria, specifically the placental transfer of antibody to newborn Nigerian babies. Tetanus toxoid antibody levels were measured in 39 mother-baby pairs in Ibadan, Nigeria and compared with 78 British mother-baby pairs. Geometric means of the ratios of cord/mother (sequestration index SI) were 0.776 for Nigerian pairs and 1.306 for British pairs, indicating a limitation in the placental transfer of tetanus toxoid in the Nigerian population. These findings confirm that there is a block in the placental transfer of anti-tetanus toxoid antibodies in African populations which will affect current immunization programmes and requires further investigation.

[Simultaneous cholecystectomy with colon surgery]

Both colorectal pathology and cholecystopathy are common disorders, especially among the elderly. Postoperative cholecystitis was well known to be associated with high morbidity and mortality. The presence of gall bladder pathology has also been reported to precipitate acute cholecystitis. In addition, these patients with gall bladder pathology may eventually need a cholecystectomy because of complications. In the above cases, some authors have suggested a simultaneous cholecystectomy at the time of colon surgery. In past 4 years, a series of 28 cases with concomitant cholecystectomy and colectomy were reviewed. The male to female ratio was 11:17, and their age ranged from 41 to 83 years old (mean age 61). The main colonic pathology was adenocarcinoma of colon and rectum (26/28). All gall bladder pathologies were diagnosed preoperatively by abdominal ultrasound, and gall stones were present in 25 of 28 cases. There were no intraoperative complications and no operative mortalities. Our data suggested that a cholecystectomy can be performed safely at the time of colon surgery, if the patient's condition is stable and contamination from colon surgery is minimal.

Hazards of angioscopic examination: documentation of damage to the arterial intima

The fiberoptic scope is increasingly used in the coronary and peripheral arteries to quantitate the degree and type of arterial obstructive disease and to inspect the results of procedures such as bypass grafting and laser irradiation of obstructive lesions. Since little is known about this instrument's potential complications, we passed a variety of fiberoptic scopes (1.8 to 3.6 mm outer diameter) in fresh postmortem pig coronary arteries and live monkey and canine peripheral arteries, and observed the intraluminal anatomy through the angioscope. No perforations were created, but ridges rising from the vascular luminal surface, avulsion of the endothelial lining, and small flaps attached at one end to the vessel wall were observed. Histologically, subintimal and medial tears were evident. Inserting large diameter scopes or making frequent passes (10 to 100) in coronary arteries increased intravascular injury. The use of small diameter flexible scopes or infrequent passes (less than 10) in the larger iliac and femoral arteries of live monkeys and dogs resulted in a lower frequency of myointimal sloughing or flap formation. Current fiberoptic scopes are not ideal angioscopes; they have a rigid tip, cannot be steered adequately, and are relatively stiff, resulting in a high probability of intraluminal injury, especially when used in small tortuous arteries. To decrease the risk of such injury, we recommend gentle manipulations while passing the scope and use of the smallest diameter scope possible. We further suggest limited use of the fiberscope, or at least limiting the number of passes in small vessels such as coronary arteries.

Potential prodrugs of phenelzine: N2-acetylphenelzine and N2-ethoxycarbonylphenelzine

This report describes experiments conducted to determine whether simple monoacylated analogues of phenelzine might act as prodrug sources of phenelzine in vivo. The data suggest that hydrolysis to phenelzine may vary between analogues and that not all analogues retain the pharmacological properties of phenelzine.

Differential photoabsorption using argon laser radiation on atherosclerotic plaque in non-hemolyzed and hemolyzed blood

Since argon laser radiation (488 to 514 nm) can vaporize human atherosclerotic plaque, we determined whether different blood media--hemolyzed versus non-hemolyzed blood--can alter photoabsorption of atherosclerotic plaque. Forty cadaveric aortic fibrous plaque samples were fitted onto small vials containing 0.02 ml of either non-hemolyzed blood or hemolyzed blood over the surface of the plaque. The distal end of a 400-mu core diameter quartz fiber was directed onto the surface of the plaque and the proximal end of the fiber was connected to an argon laser. The vaporized area and depth of plaque penetration were measured and the estimated volume of crater formation was derived. Following 2.5, 5, 10 and 20 J of laser energies, vaporized volumes were 0.12, 0.72, 0.97 and 4.09 mm3, respectively, for hemolyzed blood and were 0 (p less than 0.01), 0 (p less than 0.01), 0.92 (NS) and 4.39 mm3 (NS), respectively, for non-hemolyzed blood. Laser radiation destroys red blood cells; the higher the energies, the greater the hemolysis. Thus, different blood media such as hemolyzed and non-hemolyzed blood can alter photoabsorption of atherosclerotic plaque. Low level argon laser absorption upon plaque can occur under hemolyzed blood but not under non-hemolyzed blood. Since higher levels of argon laser energies cause greater lysis of red blood cells, comparable degrees of plaque ablation are observed under either blood medium.

Antihypertensive therapy and the concept of total cardiovascular protection

Drug-induced reduction of elevated blood pressure decreases cardiovascular mortality and morbidity in patients with moderate and severe hypertension. Furthermore, antihypertensive drug studies in mild hypertensive subjects (diastolic blood pressure 90 to 104 mm Hg) have shown protection against stroke, left ventricular hypertrophy, congestive heart failure and progression of renal damage, as well as improved patient longevity. The Hypertension Detection and Follow-up Program trial, recently carried out in the U.S., documented reduced coronary artery disease events (fatal and nonfatal) in special drug-treated patients with mild hypertension. From the standpoint of practical management and considering the ubiquity of essential hypertension, a modified stepped-care regimen advocating initial drug therapy with a beta blocker and addition of low-dose thiazide diuretic when necessary constitutes a judicious approach for widespread application. Although there are 8 orally active beta blockers currently approved in the U.S. for clinical use in systemic hypertension, only acebutolol possesses all of the salutary pharmacologic properties of cardioselectivity, intrinsic sympathomimetic activity and hydrophilicity, thereby making this compound an effective and safe beta-blocking agent for first-order management of a broad segment of the hypertensive population.

Effects of simultaneous viewing and vaporization of plaques using the steerable, laser-heated metal cap in the atherosclerotic monkey model

A steerable, fiberoptic catheter coupled to a laser light guide tipped with a metal cap was used. Four monkeys fed an atherogenic diet for 7-8 years were angiographed and were found to have extensive mural plaque in the iliac arteries. Plaque sites in these monkeys were vaporized using the laser-heated metal cap. Energies of 1.5-9 Joules were employed. Application of the energy was tangential of perpendicular to the plaque. Lased sites were examined histologically at 24 hr or at 3 months after treatment. No effect was seen at 1.5 Joules. Three to six Joules tangentially produced a superficial lesion that extended into the tunica intima. Six Joules perpendicularly produced a burn into the tunica adventitia, with damage to the vasavasorum. Nine Joules tangentially produced a burn into the tunica media. Three months after treatment, this lased site showed no stenosis or aneurysm formation.

Comparison of intravenous mexiletine and lidocaine for the treatment of ventricular arrhythmias

The efficacy and safety of intravenous loading of mexiletine was compared to lidocaine in patients with ventricular premature depolarizations (VPDs). Seventeen men and five women, average age 63 years, completed this randomized parallel study. Twelve patients received mexiletine intravenously at (5 to 10 mg/min) until greater than or equal to 95% VPD suppression was achieved or a total of 450 mg of drug was given. The average loading dose of mexiletine was 4.4 mg/kg, at an infusion rate of 0.1 mg/kg/min. Ten patients received lidocaine (1 mg/kg) given over 3 minutes, with a second similar bolus given if after 10 minutes greater than or equal to 95% VPD suppression was not achieved. Total VPDs were determined for the 60 minutes before drug administration, during drug infusion, and 60 minutes thereafter. Eleven of 12 (92%) patients receiving mexiletine were full responders (greater than or equal to 95% suppression) and one was a partial responder (greater than or equal to 75% greater than or equal to 95% suppression). Five of 10 lidocaine patients (50%) were full responders, three (30%) were partial responders, and two failed to respond. At peak suppression, mexiletine reduced mean VPD from 37 +/- 33/5 minutes (mean +/- S.D.) to 0.8 +/- 0.9/5 minutes (p less than 0.01) and lidocaine decreased mean VPDs from 28 +/- 47/5 minutes to 4.7 +/- 2.2/5 minutes (p less than 0.01). Mexiletine resulted in greater suppression of VPDs than lidocaine in terms of mean percent reduction (96% vs 68%, p less than 0.01). All lidocaine patients had therapeutic plasma levels (range 1.6 to 3.5 micrograms/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical laser recanalization of coronary obstruction. Angioscopic and angiographic documentation

Coronary angioscopy was used to assess the configuration and cross-sectional luminal area of atherosclerotic obstruction prior to and following laser recanalization in a patient at the time of bypass surgery. Angioscopy served as a useful adjunct to angiography by providing documentation of immediate improvement and patency of the laser-recanalized site.

Correlation of coronary angioscopic to angiographic findings in coronary artery disease

An Olympus ultrathin fiberscope, 1.8 mm outer diameter, was inserted intraluminally into 11 stenoses of the left anterior descending and circumflex coronary arteries in 8 patients at coronary bypass surgery. Intraluminal views were obtained by coupling the angioscope to a color video camera and videotape recorder, and compared with preoperative coronary angiographic findings in right and left anterior oblique views. Atherosclerotic plaque was observed as yellow-white mass attached onto the luminal lining, which may be large enough to virtually obliterate the vascular lumen. Angioscopy provided a topographic view and cross-sectional picture of stenosis not observed by angiography. Single-plane angioscopic cross-sectional stenotic lumens correlated well (r = 0.90, p less than 0.001) with calculated angiographic luminal narrowings. However, with subtotal obstruction, lesion length must be assessed angiographically. Coronary angioscopy can be a useful adjunct to angiography by providing the added dimension of the true cross-sectional view of obstruction.

Applicability of laser to assist coronary balloon angioplasty

Severe atherosclerotic obstructed coronary artery disease (CAD) may preclude passage of a balloon catheter for transluminal coronary angioplasty (TCA). Since lasers have been shown to effectively vaporize CAD plaque, the initial application of laser to effect a lumen large enough to accommodate the angioplasty catheter for further dilatation was explored. Eleven postmortem human CAD segments which did not permit passage of a 1.33 mm shaft diameter angioplasty catheter were studied. Argon laser radiation (14 to 90 J) transmitted via 400 micron core diameter quartz fiber onto the stenotic channel of 0.58 mm created a vaporized lumen of 1.77 mm (mean increase of 1.31 +/- 0.25 mm, p less than 0.001). The laser procedure allowed the balloon angioplasty catheter to be pushed into the stenosis. TCA was then performed (7 atm, 45 seconds) and expanded the channel to 2.12 mm (additional mean increase of 0.38 +/- 0.07 mm, p less than 0.001). In terms of percent luminal narrowing, laser radiation reduced obstruction from 80% to 45% (mean difference of -38.7 +/- 4.6%, p less than 0.001), and TCA caused a further decrease to 37% (mean difference of -9.3 +/- 1.9%, p less than 0.001). Thus, in tight atherosclerotic lesions, the laser may be useful in creating an initial opening enabling the placement of the balloon angioplasty catheter which, in turn, can further dilate the lased stenotic coronary lumen.

Argon laser radiation of human clots: differential photoabsorption in red cell rich and red cell poor clots

Since argon laser radiation (454-514 nm) can vaporize human clots, we determined whether the absorption of laser energies can differ among different types of blood clots. Thus we performed spectrophotometric studies and examined the ability of this laser to penetrate red cell rich and red cell poor clots. Fifty-four red cell rich and red cell poor clot samples, varying in depth from 1.8 to 5.0 mm, were subjected to 3, 5 and 7 watts from an argon laser beam. At a given power intensity, the deeper the red cell rich clot, the longer was the time needed to penetrate the clot. The higher the power used, the shorter was the red clot penetration time. In contrast, all power levels used up to 5 minutes did not penetrate any of the varying depths of red cell poor clots. Spectrophotometrically, the red cell rich clot had an absorption curve typical of hemoglobin pigment while the red cell poor clot, in the absence of hemoglobin, had poor absorption between 350 and 600 nm and was unable to absorb argon laser energies. Thus, the argon laser provides a therapeutic modality for human red cell rich clot dissolution but the present approach does not appear to be effective against red cell poor clots.