Nasosinusal fungal granuloma--clinical profile

Fifty cases of nasosinusal fungal granuloma were admitted under the ENT Department in a teaching tertiary care hospital in India during a thirteen-year period. Aspergillus species was found to be the most common causative fungus (29) followed by Mucorales (14), Entomophthorales (5) and Fusarium (2) species. There were 13 cases of non-invasive and 16 cases of invasive variants of Aspergillosis. In spite of intravenous amphotericin B therapy and radical surgical debridement, 81% in the invasive group showed relapse and required prolonged oral antifungal drugs and multiple surgical procedures. Among the 14 cases of Mucormycosis, all of the 10 cases who received intravenous amphotericin B and radical surgery showed complete recovery with no relapse over a period of 2 to 10 years. This is contrary to earlier published reports which suggest poor prognosis. The entomophthoromycosis received oral steroids and cotrimoxazole, and oral potassium iodide or intravenous amphotericin in case of relapse. Both the cases of Fusariosis recovered completely with oral ketoconazole.

Heterotopia of the tonsil

The histopathological finding of heterotopias or choristoma is rare. This paper describes two patients who presented with chronic recurrent tonsillitis and underwent tonsillectomy. Histological examination revealed heterotopic cartilage in the tonsil of one patient and bone in that of the other.

Anisakiasis of the tonsils

A six-year-old Indian girl presenting with clinical features of chronic recurrent tonsillitis, had a tonsillectomy. Histopathology revealed a cross-section of an Anisakis worm in the tonsil. This report documents a new location in the human host for this rare parasite.

5-Aza deoxyCytidine-induced inhibition of differentiation of spermatogonia into spermatocytes in the mouse

In order to explore the significance of DNA methylation in proliferation and differentiation of germ cells in testis, 5-aza,2'-deoxyCytidine (5-azaCdR), a hypomethylating agent, was administered in vivo to neonatal mice having only spermatogonial (premeiotic) cells. End-labeling of the MspI, HpaII, and HhaI digested DNA revealed considerable loss of methylation following the treatment. Cellular and histological preparations of the testis showed complete inhibition of differentiation into spermatocytic stage. Analysis of protein synthesis in the treated and control testis by growing the cells in 35S-Methionine medium and resolving the lysate by SDS-PAGE revealed that the programme of expression of at least 5 polypeptides (35.0, 31.5, 27.0, 22.5, and 18.0 KD) was altered as a result of 5-azaCdR incorporation. It appears that DNA methylation plays a critical role in the differentiation of gonia into primary spermatocytes.

Decreased cerebral glucose metabolism in patients with brain tumors: an effect of corticosteroids

The authors measured cerebral glucose metabolism (CMRglu) using [18F]fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in patients with brain tumors to evaluate the effect of exogenous corticosteroids (in this instance, dexamethasone) on glucose metabolism. Fifty-six FDG-PET studies obtained in 45 patients with unilateral supratentorial brain tumors were analyzed. Patients with brain tumors were divided into three groups: 1) patients with cushingoid symptoms, who had been treated with combinations of radiotherapy and chemotherapy taking oral dexamethasone; 2) patients not taking dexamethasone but treated with radiotherapy; and 3) patients not taking dexamethasone who had not been treated with radiotherapy. Serial FDG-PET scans were obtained in eight of the cushingoid patients. Glucose metabolism was measured in the contralateral cerebral and ipsilateral cerebellar hemispheres in patients and compared to measurements taken from 19 normal volunteers. The authors found that in the cushingoid brain tumor patients there was a marked reduction in CMRglu compared to normal volunteers and other brain tumor patients (Kruskal-Wallis test; p 0.001). In the majority of patients who had serial FDG-PET scans, there was a decline in glucose metabolism over time and in one patient, in whom dexamethasone was reduced in dosage, there was a subsequent increase in CMRglu. The authors conclude that there is a generalized reduction in CMRglu in brain tumor patients taking dexamethasone compared to other brain tumor patients and normal volunteers, and that this effect is independent of radiotherapy, concurrent anticonvulsant medication, and transhemispheric functional disconnection (transhemispheric diaschisis).

Correlative morphologic and functional imaging for diagnosis, staging and follow up in AIDS: an overview

The immunocompromised patient can be affected by different opportunistic infections and tumors, that can involve all organ systems, and particularly, the central nervous system, the respiratory system, the gastrointestinal tract. The extreme variability of AIDS presentations requires a specific preparation and cooperation between the different diagnostic imaging specialists and a close collaboration with the clinicians. With AIDS, different morphologic and functional imaging techniques can be used for detection of disease sites, assessment of the extent of the disease and monitoring of disease changes over time and response to treatment. The complexity of AIDS presentations is such that full integration of the complementary information obtained with different techniques could be most useful. Image registration (coregistration, fusion) indicates approaches where precise spatial cross-references are obtained, in order to combine the information acquired with different imaging modalities, in particular by blending morphologic CT/MRI data with functional SPET/PET data. In this paper, an overview of the developments in the field of "image fusion" follows some comments on the results of morphologic and functional assessment of brain, chest and abdominal diseases in the course of AIDS, as illustrative examples of the potential benefits of multimodality image correlation.

Glycine decarboxylase: protein chemistry and molecular biology of the major protein in leaf mitochondria

The four component proteins of the glycine decarboxylase multienzyme complex (the P-, H-, T-, and L-proteins) comprise over one-third of the soluble proteins in mitochondria isolated from the leaves of C3 plants. Together with serine hydroxymethyltransferase, glycine decarboxylase converts glycine to serine and is the site of photorespiratory CO2 and NH3 release. The component proteins of the complex are encoded on nuclear genes with N-terminal presequences that target them to the mitochondria. The isolated complex readily dissociates into its component proteins and reassociates into the intact complex in vitro. Because of the intimate association between photosynthesis and photorespiration, the proteins of the complex are present at higher levels in leaves in the light. The expression of these genes is controlled at the transcriptional level and the kinetics of expression are closely related to those of the small subunit of Rubisco. Deletion analysis of fusions between the promoter of the H-protein of the complex and the reporter gene beta-glucuronidase in transgenic tobacco has identified a region responsible for the tissue specificity and light dependence of gene expression. Gel shift experiments show that a nuclear protein in leaves binds to this region. Glycine decarboxylase has proven to be an excellent system for studying problems in plant biochemistry ranging from protein-protein interactions to control of gene expression.

Brain regional distribution pattern of metabolite signal intensities in young adults by proton magnetic resonance spectroscopic imaging

Proton magnetic resonance spectroscopy (1H-MRS) is evolving from single-volume localized acquisitions to multiple-volume acquisitions using magnetic resonance spectroscopic imaging (1H-MRSI). The normal regional patterns of 1H-MRSI-detectable metabolite signal intensities have yet to be established. We studied 13 healthy young adults with a multiple-section 1H-MRSI technique. The metabolite signals measured were N-acetylaspartate (NA), choline-containing compounds (CHO), creatine-phosphocreatine (CRE), and lactate. Ten neuroanatomic regions (nine bilateral) were identified in gray matter, white matter, and basal nuclei. Analysis of the data led to the following conclusions: (1) NA and CHO signals from centrum semiovale (CSO) can be used as a normalizing factor to reduce intersubject variability due to external causes; (2) in normal human brain, there is no left versus right asymmetry in the regions studied; (3) statistically significant patterns of signal distribution of NA, CHO, and CRE can be identified in normal human brain; and (4) CSO-normalized metabolite signal intensities and metabolite ratios complement each other for the detection of significant regional differences.

PET-FDG of pleomorphic xanthoastrocytoma

A young patient with pleomorphic xanthoastrocytoma (PXA), a usually benign cerebral tumor, had two recurrences in a short time period. The clinical, pathological and neuroradiological features, including PET with [18F]-fluorodeoxyglucose (FDG), are presented. The PET-FDG study revealed the recurrent tumor to be hypermetabolic. The diagnosis was confirmed histopathologically. As the clinical outcome of patients harboring PXA is not easy to predict because of possible recurrence and/or transformation into more aggressive gliomas, we discuss the predictive indicators of more aggressive clinical behavior.

An overview of the CERC ARTEMIS project

The basic premise of this effort is that health care can be made more effective and affordable by applying modern computer technology to improve collaboration among diverse and distributed health care providers. Information sharing, communication, and coordination are basic elements of any collaborative endeavor. In the health care domain, collaboration is characterized by cooperative activities by health care providers to deliver total and real-time care for their patients. Communication between providers and managed access to distributed patient records should enable health care providers to make informed decisions about their patients in a timely manner. With an effective medical information infrastructure in place, a patient will be able to visit any health care provider with access to the network, and the provider will be able to use relevant information from even the last episode of care in the patient record. Such a patient-centered perspective is in keeping with the real mission of health care providers. Today, an easy-to-use, integrated health care network is not in place in any community, even though current technology makes such a network possible. Large health care systems have deployed partial and disparate systems that address different elements of collaboration. But these islands of automation have not been integrated to facilitate cooperation among health care providers in large communities or nationally. CERC and its team members at Valley Health Systems, Inc., St. Marys Hospital and Cabell Huntington Hospital form a consortium committed to improving collaboration among the diverse and distributed providers in the health care arena. As the first contract recipient of the multi-agency High Performance Computing and Communications (HPCC) Initiative, this team of computer system developers, practicing rural physicians, community care groups, health care researchers, and tertiary care providers are using research prototypes and commercial off-the-shelf technologies to develop an open collaboration environment for the health care domain. This environment is called ARTEMIS--Advanced Research TEstbed for Medical InformaticS.

Oocytes from pachytene to dictyotene can easily be analysed in neonatal rodents

We have investigated the dynamics of meiotic prophase I in neonatal ovaries from different wild rodent species, from a laboratory strain of Mus musculus and from Mus musculus x Mus spretus F1 hybrids. We found that almost all stages of prophase I were regularly present in neonatal ovaries from these species and that their transcriptional activity can be assessed by [3H]-uridine incorporation, indicating that postnatal analysis of meiotic chromosomes and synapsis may be conducted as an alternative to the investigation of foetal ovaries.

External laryngeal trauma: analysis of thirty cases

A retrospective analysis of thirty patients with external laryngeal trauma was performed to assess the type and extent of injuries commonly seen as well as the outcome following treatment. Outcome was assessed both in terms of voice and airway. Major laryngeal injuries (19 cases) outnumbered minor injuries (11 cases). A good correlation exists between the symptoms of haemoptysis and stridor at presentation and severity of the injury (p = 0.002). Early surgical intervention is associated with better outcome (p = 0.01). However there is no statistically significant difference in outcome between major and minor injuries (p = 0.3) indicating that other factors are operative in determining outcome. Based on our findings a management strategy for patients with external laryngeal trauma is outlined.

Medical therapy of rhinosporidiosis with dapsone

Clinical, histopathological and ultrastructural studies in three cases of rhinosporidiosis show complete remission of infection within one year of therapy with dapsone. Light and electron microscope studies confirmed arrest of the maturation of the spores and accentuated granulomatous response with fibrosis following dapsone therapy.

Profuse epistaxis: an argument for conservative medical management

A review of 10 years' experience of all patients with profuse epistaxis requiring hospitalisation in a tertiary care centre in India is presented. There were 106 patients among which only 72% of cases had associated medical illness. Hypertension (44%) and bleeding diathesis (11%) were found to be the most frequently associated aetiological medical conditions noted in this study. Although there is controversy regarding the optimum treatment in profuse epistaxis in literature, our experience suggests that it can be successfully managed with conservative medical management alone and surgical intervention with its potential complications may not be necessary in most cases.

Mammalian sex chromosomes. VI. Synapsis in the heterochromatin-rich X chromosomes of four rodent species, Mus dunni, Bandicota bengalensis, Mesocricetus auratus, and Nesokia indica

This study analyzes the progression of chromosomal synapsis in female meiosis of four rodent species, Mus dunni, Bandicota bengalensis, Mesocricetus auratus, and Nesokia indica. Special attention has been paid to understand the mode of pairing between heterochromatin-rich X chromosomes. The ovaries were obtained from newborn individuals instead of fetuses. In all but M. auratus, day 0 ovaries provided almost all the prophase stages at varying frequencies. In B. bengalensis and M. dunni the entire X chromosomes were paired including the heterochromatin. In M. auratus and N. indica, the heterochromatic arms in a proportion of X bivalents, however, were only partially synapsed. It appears that in these two species heterochromatin association is either delayed or short lived.

Alterations in oropharyngeal flora in patients with a nasogastric tube: a cohort study

OBJECTIVE

To determine whether or not the presence of a nasogastric tube causes a change in the bacterial flora in the oropharynx.

STUDY DESIGN

Cohort (prospective) design with concurrent control.

SETTING

General Surgical and Ear, Nose, and Throat Units of a tertiary care hospital.

PATIENTS

Sixteen patients with and 14 patients without a nasogastric tube.

INTERVENTIONS

Patients scheduled to undergo surgery under general anesthesia with endotracheal intubation were eligible for inclusion in the study. From these patients, a study cohort of 16 consecutive patients who were to have nasogastric tube intubation and 14 patients who were not to have nasogastric intubation were enrolled. All patients had a high oropharyngeal swab taken for bacteriologic culture just before surgery. The swab of the oropharynx for culture was repeated after 48 to 72 hrs. The type of organism grown was identified and compared between and within the two groups.

RESULTS

There was a significant increase in the frequency of colonization of the oropharynx by pathogenic Gram-negative bacteria after 48 to 72 hrs of nasogastric intubation in comparison with the preintubation level (p < .01) as well as in comparison with the group that did not have nasogastric intubation (p < .001). The pathogens included Pseudomonas, Klebsiella, Proteus and Escherichia coli. There was also a tendency for suppression of normal flora. There was no significant change in the flora of the control group of patients who did not have nasogastric intubation. The two groups were comparable with respect to age, gender, severity of underlying illness, and use of prophylactic perioperative antibiotics.

CONCLUSIONS

The presence of nasogastric tubes in patients predisposes to colonization by Gram-negative pathogenic bacteria within 48 to 72 hrs.

Mapping of brain tumor metabolites with proton MR spectroscopic imaging: clinical relevance

Brain tumor metabolism was studied with hydrogen-1 magnetic resonance spectroscopy and positron emission tomography with fluorine-18 fluorodeoxyglucose in 50 patients. N-acetylaspartate (NAA) was generally decreased in tumors and radiation necrosis but was somewhat preserved at neoplasm margins. Choline was increased in most solid tumors. Solid high-grade gliomas had higher normalized choline values than did solid low-grade gliomas (P < .02), but the normalized choline value was not a discriminator of tumor grade, since necrotic high-grade lesions had reduced choline values. Serial studies in one case showed an increase in choline as the glioma underwent malignant degeneration. Choline values were lower in chronic radiation necrosis than in solid anaplastic tumors (P < .001). In two cases studied before and after treatment, clinical improvement and a reduction in choline followed therapy. Lactate is more likely to be found in high-grade gliomas, but its presence is not a reliable indicator of malignancy.

Effects of radiation on hearing in patients with malignancies of head and neck

Patients with normal hearing at the start of radiation were tested for hearing during (30 GY) and at the end of radiation therapy (45-60 GY) in order to determine if there was any alteration in their pure tone hearing thresholds. A significant increase in the hearing threshold was found at high frequencies at the end of therapy. At the end of the course of radiation, clinical findings suggestive of middle ear changes due to radiation were seen in 33% of the ears. Patients whose ears are included in the field of radiation may have to be forewarned to expect a loss in their acuity of hearing, especially those whose professional life may depend on it.

Maxillary sinus fusariosis in immunocompetent hosts

We report the first known cases of Fusariosis of maxillary sinus with granuloma and oro-antral fistula in two immunocompetent hosts. Fusarium solani was demonstrated in the direct microscopic examination and isolated in heavy growth from the biopsy materials. Both these patients were successfully treated with oral ketoconazole (200 mg daily) for three weeks followed by a Caldwell-Luc operation. Ketoconazole was continued for two months post-operatively.

Laryngeal stridor in myasthenia gravis

Two patients with laryngeal stridor secondary to myasthenia gravis are reported. The cause of bilateral abductor weakness in myasthenia is discussed; anticipation of the stridor in myasthenic patients is highlighted.

Medical management of pseudocyst of the auricle

Four male patients with pseudocyst of the auricle were successfully treated with oral corticosteroids. This condition is an asymptomatic, non-inflammatory, cystic swelling, usually located in the scaphoid or triangular fossa of the anti-helix which if untreated, leads to deformity of the pinna. All successful methods of treatment described in the literature so far have been invasive. All four patients in the above series responded to oral steroid therapy alone.

Obliterative otosclerosis

An analysis of 420 consecutive cases of obliterative otosclerosis seen in the Christian Medical College Hospital, Vellore is presented. The proportion of truly obliterative otosclerosis is 33.09 per cent (139 ears). Our male to female ratio in truly obliterative otosclerosis is 1.48:1, while in the non-obliterative group it is 1.34:1. The mean age at onset in the obliterative group was 19.14 while in the non-obliterative group it was 25.60. This is statistically significant (P less than 0.001). The age at presentation was 25.90 in the obliterative group while in non-obliterative group it was 30.86; this is also statistically significant (P less than 0.001). However the time interval between the age at onset and the age at presentation is not statistically significant.

Nasofacial conidiobolomycosis

A case of Nasofacial Zygomycosis in a 15-year-old male patient from South India is reported. This patient had typical thickening of the nasofacial mucosa and the skin overlying it. The diagnosis was confirmed with fungal cultures. Although initially good response to treatment with potassium iodide was achieved, later the response was unsatisfactory, probably partly due to irregularity in treatment. Treatment with sulphamethoxazole--trimethoprim and prednisolone combination has resulted in remarkable improvement.

Mammalian sex chromosomes. III. Activity of pseudoautosomal steroid sulfatase enzyme during spermatogenesis in Mus musculus

Parallel to the inactivation of the X chromosome in somatic cells of female, the male X in mammals is rendered inactive during spermatogenesis. Pseudoautosomal genes, those present on the X-Y meiotically pairable region of male, escape inactivation in female soma. It is suggested, but not demonstrated, that they may also be refractory to the inactivation signal in male germ cells. We have assayed activity of the enzyme steroid sulfatase, product of a pseudoautosomal gene, in testicular cells of the mouse and shown its presence in premeiotic, meiotic (pachytene), and postmeiotic (spermatid) cell types. It appears that, as in females, pseudoautosomal genes may escape inactivation in male germ cells also.

Effect of nasogastric tubes on the nose and maxillary sinus

OBJECTIVE

To estimate the proportion of patients who develop radiologic evidence of maxillary sinus inflammation among those who are maintained on nasogastric (NG) tubes after major surgery.

DESIGN

Prospective case series.

SETTING

Patients were drawn from the general surgical and ear, nose, and throat units of a tertiary care hospital.

METHOD

All patients undergoing major surgery with or without a concurrent tracheostomy, in whom an NG tube was retained for greater than or equal to 48 hrs, were examined clinically and radiologically for evidence of maxillary sinus inflammation.

RESULTS

Sixty-five patients were studied. Twenty patients had a concurrent tracheostomy and 45 patients were without tracheostomy. Only 10% of the patients in the tracheostomy group developed radiologic evidence of sinus inflammation, as compared with 50% in the nontracheostomy group (p less than .05). The proportion of patients who developed clinical evidence of rhinitis was about 75% in either group. However, none of the patients in the study had clinical evidence of maxillary sinusitis. There was no correlation between the age of the patient, sex, use of broad-spectrum antibiotics, or duration of NG intubation with the onset of sinus inflammation.

CONCLUSIONS

The presence of NG tubes predisposes to nasal and maxillary sinus inflammation. Sinonasal symptoms of clinical sinusitis may not be present even when radiologic evidence of inflammation is evident. In patients with tracheostomy, the frequency of maxillary sinus inflammation is significantly lower than in those patients without tracheostomy.

Aetiological profile of paediatric laryngeal stridor in an Indian hospital

The case records of 180 infants and children with stridor were reviewed to note their clinical profile. We found that cases of acute stridor outnumbered cases of chronic stridor. The aetiology was congenital in 32.2% and acquired in 67.8%. Laryngomalacia (19.4%) was the commonest congenital cause. Laryngotracheobronchitis and diphtheria were the commonest infectious causes (35%). Tracheostomy was performed in 25% of cases, the most frequent indication being bilateral abductor paralysis. The problems peculiar to developing countries that influence the clinical status of a child in stridor are discussed.

Chronic suppurative otitis media: complicated versus uncomplicated disease

To determine prognostic factors in patients with chronic otitis media who develop suppurative complications, we performed a retrospective study of all patients with chronic suppurative otitis media who underwent mastoid surgery between the years 1981 and 1989. Patients who developed complications were compared with those who did not with respect to six prognostic variables. The results indicated that patients with complications were younger (p less than 0.001), had shorter duration of ear discharge (p less than 0.001), were more likely to have pars tensa perforations (p less than 0.05), and had a higher degree of mastoid sclerosis in the operated and contralateral ears (p less than 0.001). The presence of cholesteatoma and the sex of the patient were of no prognostic value. Bacteriology of CSF and pus specimens from patients who developed intracranial complications mostly revealed mixed flora (62.9%). Proteus species was the most frequent isolate (34%) and anaerobes were present in 21.3% of specimens. Mastoid abscess occurred in more than half the patients in the complicated group. Brain abscess (57.4%) was the most frequent intracranial complication. On the basis of our findings we recommend that risk factors in patients with chronic suppurative otitis media be identified early to enable effective measures to be taken to eradicate the disease.

Pneumatization of the paranasal sinuses (maxillary and frontal) in cleft lip and palate

A comparative study of roentgenograms of the paranasal sinuses between 37 patients with cleft lip and palate and 37 control subjects of the same age group was done using a planimeter. The results indicate that there is no statistical difference in the sizes. The paranasal sinuses increased in size with age in patients as well as in control subjects.

Role of 1q trisomy in tumorigenicity, growth, and metastasis of human leukemic B-cell clones in nude mice

In order to investigate the association between various karyotypes of human tumor cells and biological behavior of tumors such as tumorigenicity, rate of growth, and the capacity to form metastasis, six chromosomally distinctive clones were isolated from an Epstein-Barr virus-transformed human chronic lymphocytic leukemic B-cell line which progressively grew and metastasized in irradiated nude mice. When inoculated into nude mice one clone (D10-1) with the karyotype of 46,XY,dup(1)(q11----q32) was more tumorigenic, grew faster, and produced more metastases than the other five clones. When mixtures of different clone-derived cells were grown in vitro or inoculated s.c. into nude mice the proportion of D10-1 cells was higher than their expected numbers in the cultures, s.c. tumors, and splenic and lymph nodal metastases. The growth and metastatic potential of the D10-1 clone were inhibited when cells from this clone were mixed with one or more clones that had slower growth. Duplication of 1q has been observed as a secondary aberration in human hematological malignancies and solid cancers. Our results demonstrate that duplication of the chromosome segment of 1q11----1q32 is associated with advantages in proliferation and metastasis formation.

Roentgen examination of maxillary sinus, antral puncture and irrigation--a comparative study

The various radiological findings of maxillary sinus were compared to those at antral puncture and irrigation in patients with chronic maxillary sinusitis. It was noted that roentgen findings of opacity and fluid level of the maxillary sinus are definite evidences of sinus infection and a mucosal thickening is not an indication of sinus infection.

Inherited nasal and laryngeal degenerative chondropathy

Four rare cases of congenital saddle-nose deformity and slowly progressive degeneration of laryngeal cartilages with stenosis are described. The term inherited degenerative chondropathy is suggested for this disease entity. To our knowledge this is the first article on such a disease.

A unilateral mesenchymal disorder of the head

A hitherto undescribed group of lesions consisting of cystic bony lesions, exostosis, fibromatous lesion, unilateral tonsillar hypertrophy, epidermoid cyst (cholesteatoma) and hyperplasia of the mandible confined to the left side of the face is reported. The case may represent a variant of the Proteus syndrome.

Muscle receptors: content of some of the extrinsic and intrinsic muscles of the larynx in the bonnet monkey (Macaca radiata)

The number of muscle receptors and in particular the muscle spindle content of some of the intrinsic and extrinsic laryngeal muscles was evaluated, using bonnet monkeys (Macaca radiata). The technique of Barker and Ip [J. Physiol. (Lond) 169:73-74, 1963] was used to stain the muscle receptors. The results indicate that the intrinsic laryngeal muscles were devoid of muscle spindles. The extrinsic laryngeal muscles that were examined contain muscle spindles, though their density is less than that reported in the spindle-rich muscles like the rotators of the head and some of the intrinsic muscles of the hand (Cooper in: Structure and Function of Muscle, Vol. I, G.H. Bourne, ed, Academic Press, New York and London, 1960).

Microscopically diagnosed head and neck cancers in the University Hospital, Kuala Lumpur

A retrospective study of 1000 cases of microscopically diagnosed head and neck cancers in the University Hospital, Kuala Lumpur was done. Head and neck neoplasms comprise 7.1% of all tumours diagnosed in this Hospital and the commonest sites of involvement are the nasopharynx (29.1%), cervical lymph nodes (22.6%), oral cavity (10.2%), thyroid (8.2%) and skin (6.5%). Histologically, 87% of tumours are epithelial in nature. The results of this study show that nasopharyngeal carcinoma is commonest in Chinese males, while oral and laryngeal malignancies occur more frequently in Indians.

Vasomotor rhinitis--atrophic rhinitis: two ends of an autonomic spectrum

A hypothesis is put forward based on clinical observations and treatment modalities in vasomotor non-allergic rhinitis (V.M.R.) and primary atrophic rhinitis (P.A.R.). The hypothesis postulates that (1) V.M.R. and P.A.R. are two diseases at the ends of an autonomic spectrum (2) The anterior nasal aperture, its dimensions and sensory receptors play a vital role in the etiopathogenesis of both the conditions through reflex autonomic action.

DNase I nick translation in situ on meiotic chromosomes of the mouse, Mus musculus

DNase-I-sensitive sites have been located on the meiotic chromosomes of the mouse, Mus musculus, by the in situ DNase I nick-translation method. We find that: (1) of all the cell types studied, pachytene nuclei are the most sensitive to DNase I; (2) in diplotene the nicks occur preferentially in the vicinity of chiasmata; (3) the sex chromosomes are also sensitive to the enzyme despite their transcriptional quiescence; and (4) in the sex bivalent the nicks are primarily observed in the putative region of recombination. We conclude that, in addition to discriminating between the transcriptionally active and inactive states of chromatin, DNase I identifies recombination-specific chromatin changes in meiotic prophase.