Genetic and host-associated differentiation within Thrips tabaci Lindeman (Thysanoptera: Thripidae) and its links to Tomato spotted wilt virus-vector competence.

Of eight thelytokous populations of onion thrips (Thrips tabaci) collected from potato (three populations), onion (four) or Chrysanthemum (one) hosts from various regions of Australia, only those from potato were capable of transmitting Tomato spotted wilt virus (TSWV) in controlled transmission experiments. Genetic differentiation of seven of these eight populations, and nine others not tested for TSWV vector competence, was examined by comparison of the DNA sequences of mitochondrial cytochrome oxidase subunit 1 (COI) gene. All Australian populations of T. tabaci grouped within the European 'L2' clade of Brunner et al. (2004). Within this clade the seven populations from potato, the three from onion, and the four from other hosts (Chrysanthemum, Impatiens, lucerne, blackberry nightshade) clustered as three distinct sub-groupings characterised by source host. Geographical source of thrips populations had no influence on genetic diversity. These results link genetic differentiation of thelytokous T. tabaci to source host and to TSWV vector capacity for the first time.

Malignant fibrous histiocytomas of the larynx--report of two cases.

Malignant fibrous histiocytoma of the larynx is a rare entity. It is even more infrequent for the tumour to arise from a specific location on the larynx namely the vocal cords. We report two cases of vocal cord malignant fibrous histiocytoma, one in a 27-year old man who underwent frontal partial laryngectomy, and the other in a 57-year old man who was managed with total laryngectomy. Both patients remain disease-free after 5 years of follow-up. We present a discussion of the available literature on this subject. As these tumours occur very infrequently, no one centre is able to acquire the prerequisite amount of experience to be able to lay down firm scientifically based guidelines on the management of these tumours. It is thus inevitable that whatever evidence we have is purely anecdotal in nature.

Acetowhite staining in the detection of laryngeal disease.

The acetowhite staining reaction is widely used as a reliable adjunct to the diagnosis of malignant lesions in gynaecology, but its application in vocal cord lesions has not been assessed before. The use of the acetic acid staining reaction in selecting sites for sampling on the vocal cord is considered in this study. A 3% acetic acid solution was applied intraoperatively before biopsy to the larynx of eight patients who had either diffuse erythematous or polypoidal vocal cords. Attempts were made to correlate the degree of acetowhitening with the underlying histological findings. There was a very poor correlation between acetowhitening and the histological diagnosis, and very poor demarcation between stained and unstained areas. The application of acetic acid is not a useful adjunct to biopsy selection in the larynx.

Free rib graft reconstruction of the mandible: a forgotten option?

Eleven patients underwent primary mandibular reconstruction following resection of a head and neck squamous cell carcinoma. Reconstruction consisted of a free rib graft and a pectoralis major myocutaneous flap. One rib graft failed and one graft, although successful, required removal during a wider resection for tumour recurrence. A further three patients have died since operation, two from tumour recurrence and one from unrelated medical causes. Six patients have undergone long-term follow-up of between 22 and 78 months with a mean of 51 months. They have oral continence, take a normal or semisolid diet, and have satisfactory cosmesis. We present the first long-term follow-up of a series of patients undergoing mandibular reconstruction with a free rib graft and pectoralis major myocutaneous flap.

Invasive aspergilloma of the skull base.

Aspergillus infection originating in the nasal cavity or paranasal sinuses is a rare cause of benign, locally invasive disease affecting the skull base. We describe a case in which extensive disease led to bilateral proptosis and invasion of the anterior cranial fossa.

Staple gun in the surgery of hypopharyngeal diverticula.

There have been many approaches advocated over the years for the surgical management of hypopharyngeal diverticulum, and this is a reflection of the absence of an ideal method both in terms of the surgical technique and of the frequency and severity of complications. Further experience with the use of the surgical staple gun is presented together with a discussion of its use in comparison with other operative methods. The ease and speed of the technique combined with a negligible complication rate suggest that it is a viable method for the management of large diverticula.

Cervical abscess: a life-threatening complication of infectious mononucleosis.

The former view of infectious mononucleosis as an invariably benign disease has been modified in recent years by reports of life-threatening complications. A case is presented of a deep cervical abscess complicating infectious mononucleosis which came close to a fatal conclusion. The implications for the management of the illness are discussed in the light of this rare event, no exactly similar instance of which has been recorded.

Thorotrast granuloma--a renascence.

A case of cervical thorotrast granuloma and its surgical complications is presented. The properties and usage of thorotrast and its later complications are described, and the management of the complications is discussed. It is emphasized that there is usually a long latent period between thorotrast exposure and the advent of complications and perhaps more cases of similar difficulty may be anticipated in the future.

The use of a stapling instrument in the surgery of hypopharyngeal diverticula.

There have been no early complications following the use of a stapling instrument in the surgery of hypopharyngeal diverticula, and, in addition, the technique is very simple. It is too early to know what the recurrence rate might be but it is the author's intention to persevere with this technique since it promises to represent a considerable advance on the traditional operation. It is hoped to report more extensive results at a future date.

Cerebrospinal fluid rhinorrhoea and its management.

A series of 100 cases of cerebrospinal fluid rhinorrhoea has been analysed with reference to the incidence and pattern of meningitis in order to formulate a rationale for the future management of such cases. Most cases are best managed conservatively for the first 14 days during which the majority resolve spontaneously. Of those requiring surgery, the trans-ethmoid/sphenoidal route of repair is preferred except in certain specified circumstances. The high incidence of meningitis in cerebrospinal fluid rhinorrhoea following nasal or trans-sphenoidal surgery probably demands early operation by craniotomy.

Noise-induced hearing loss and orchestral musicians.

Noise-induced hearing loss (NIHL) is well reported among devotees of rock 'n' roll music, but less attention has been focused on players of orchestral music. Sound pressure levels have been recorded from within orchestras during performances, and audiometry has been carried out on orchestral musicians. Short-lasting peaks of sound of high amplitude were found to occur, and some players had audiometric changes consistent with NIHL. However, in practice, there seemed to be no threat to the players' continued livelihood, although the additive effect of presbyacusis in later life poses a potential problem. The difficulties of prevention of NIHL and the attenuation of the high sound levels of orchestras do not seem to be completely soluble.

Isolation of mumps virus from the inner ear after sudden deafness.

A 26-year-old woman with bilateral otosclerosis underwent right stapedectomy with an excellent result. One year later, however, she developed symptoms of mumps and within two days was completely deaf in the right ear. Prompt surgical exploration excluded a complication of the otosclerosis and a perilymph fistula, but culture of a sample of perilymph grew mumps virus. The case provides direct evidence of a relation between mumps virus infection and inner-ear damage.