Satisfaction with care and the utilization of dental services at a neighborhood health center.

The purpose of this research was to develop further information relevant to the problem of utilization of dental services at neighborhood health centers.  The research objectives were: (1) A descriptive assessment of the utilization trends of the population served by a neighborhood health center; (2) Some determination of any possible correlation between failed appointments and patients' satisfaction with dental care; and, (3) Some exploration of possible reasons for non-utilization of scheduled dental appointments by a sample of patients from the neighborhood health center who report a history of previous dental treatment.  From dental clinic daily appointment sheets, an assessment of utilization trends of a neighborhood health center population for a seven-month period (jon trends of a neighborhood health center population for a seven-month period (June 1, 1973 to December 31,1973) was obtained.  In addition, analyses of patient treatment records and information obtained from personal interviews with 40 individuals from the health center population facilitated the completion of the second and third research objectives.  The results indicated: (1) Compared to the findings of earlier research,-3 the reported ratio of broken to total appointments scheduled for this study population was substantially lower; (2) There is a rather strong relation between satisfaction with care and the utilization of dental services at the neighborhood health center studied; (3) Satisfaction with care is dependent upon a number of factors; and (4) Reasons given for nonutilization of scheduled dental services are practical ones, of which some are also reflected in the reasons given ofr dissatisfaction with dental care.


Attitudes among dental students concerning dental public health as a professional career.

The report has presented information about attitudes concerning Career in Dental Public Health of 722 dental students representing 19 American schools of dentistry.  "Attitude" was operationally defined by the "attractiveness" of the concept as measured in 1969 with the semantic differential technic (exciting-dull, rewarding-frustrating, successful-unsuccessful).-6  The "attractiveness" of Career in Dental Public Health was compared with that of two other concepts: Career in Private Practice and Career in Dental Education.  Specifications were made according to year of study, individual school, type of school (public or private control), geographical region of university town, and dental school relation to graduate schools of public health.  Observed differences in student attitudes at the different schools were analyzed in relation to the emphasis each school placed in 1968-69 on instruction in (dental) public health, and to the amount of experieniced instruction in (dental) public health by each individual class.


The effect of the new federalism on education for dental public health.

The interest of this paper was to explore the effects of the "New Federalism" on the future dental public health training.  It has indicated that there is a need for an immediate source of funding in order to avoid curtailment of dental public health training programs, and an adverse change in the composition of future students.  Further, the national character of public health training was recognized and the federal level of government was looked to anxiously in order to observe what will happen with the training and general purpose monies.  Only with a definite and long-term commitment from government, whether it be centrally or regionally located, can dental public health programming flourish once again.


Educational program  n dental public health at schools of public health as of fall 1973.

A letter of inquiry from a fictious dentist, requesting applications and information regarding training in dental public health, was sent to each of the 19 accredited Schools of Public Health. The purpose of the survey was to determine the manner in which the schools respond to a letter of inquiry from a dentist and to determine, from the material included in the response, what type of program in dental public health, if any, each school had. All 19 schools responded, but the type and quality of the responses varied greatly. Some schools answered the questions fully and others ignored them. From the bulletins of the schools and other material contained in the responses, seven schools were determined to have what could be termed viable programs in dental public health. Two of the seven programs are administratively independent with full-time faculty as directors of their programs; three of the programs receive their major input in dental public health from an affiliated dental school; one program's input of dental public health is provided by the school of public health; and one program has an affiliation with a dental school, but the major portion of the input for dental public health during the year of preparation for the degree of MPH is provided in the school of public health. There are seven schools of public health with eight full-time faculty who are public health dentists, although only three of the faculty spend a substantial portion of their time in activities related to dental public health. Five schoolshave no public health dentist on the faculty and they have a total of 33 part-time faculty at the rank of assistant professor or higher and a total of 36 part-time faculty with a rank lower than instructor. Twelve of the schools of public health still require only a minimum of an academic year for a dentist to receive the degree of MPH and only one school requires more than a calendar year. Only five schools require field-experience in order for a dentist to receive his degree of MPH. Most schools, it appears, do not provide a program for dentists which meets the standards established by the American Public Health Association or the American Board of Dental Public Health. It is time to question the blanket acceptance by the Council on Dental Education of the American Public Health Association's accreditation of Schools of Public Health for meeting the academic requirements in the specialty of dental public health.


Dental students paired for DAU training.

In summary, policy has been established at the University of Oklahoma College of Dentistry which pairs dental students for their clinical experiences during the first two years of their dental education--alternating the roles of dentist and assistant. A modified program for third-year dental students has been designed which includes assignment of trained dental assistants and some limited solo operations as well as a continuation of the pairing. It is anticipated that this approach will also be employed during the fourth year with more emphasis being placed upon utilization of trained assistants. The formal DAU course is given first semester of freshman year; and the principles are reinforced in each subsequent year. The advantages of this program seem to be (1) early integration of DAU principles into the curriculum, (2) increased efficiency while operating in pairs, (3) experience for training assistants for further private practice, (4) reduced appointment time for patients and (5) better use of clinical space. The application of the pairing concept will be continuously reevaluated to determine if such benefits are forthcoming.


Fever of unknown origin and the value of gallium-67 and technetium-99M for defining abnormality of the spleen: a case report.

A three-year-old white female with acute promyelocytic leukemia developed persistent fever after successful induction-remission therapy; many large monilial abscesses were later found in the grossly enlarged spleen. Although the technetium-99M sulfur colloid scan prior to splenectomy suggested only a slight abnormality of the spleen, the gallium-67 citrate scintigraph showed a marked increase in gallium accumulation. The disparate results of the scanning techniques utilized in this patient suggest that it may be necessary to use more than one type of radiopharmaceutical to define an enlarged spleen, as well as the pathological process responsible for its enlargement.


An analysis of controlled mandibular movement.

Kinematographic traces enable an assessment of jaw movements in the sagittal and coronal planes and the relationship of centric relation to centric occlusion can be determined. Centric relation in this context does not necessarily imply the ligamentous position but rather to an actively obtained physiological border position possibly corresponding to the retruded direct contact position. This position in normal subjects is either postero-inferior to or coincident with centric occlusion. Normal subjects were able to make lateral movements of the jaws to and from centric occlusion on either side and certain subjects were able to describe a plateau in or about the horizontal position of centric occlusion. Rhythmic traces showed that opening and closing movements of the jaws could be made in about 550 msec and reflex jaw opening was usually elicited after centric occlusion had been achieved. The significant correlation coefficients found by measuring the angles of opening, terminal opening and closing indicated that jaw movement was integrated. The TMJ series differed from the normal series in nearly all phases of jaw movement recorded. Centric relation was found to be lateral and antero-inferior to centric occlusion. On the side of the first interceptive tooth contact the patient was not able to return the jaws to centric occlusion. Intermittent traces indicated that there was no significant correlation between the angles of opening, terminal opening and closing suggesting that jaw movement were incoordinated. This was reflected in rhythmic traces which were considerably longer than those of the normal series. This increase in duration was found to be due partially to centric slides and partially to asynergistic movements of the mandible. The jaw-opening reflex was not usually elicitable. It is considered that in the TMJ series centric occlusion is a strained position and is usually lateral to and postero-superior to centric relation. This relationship of centric occlusion to centric relation is the reverse of normal relations and indicates that the mandible is displaced in centric occlusion. In general, patients with the TMJ syndrome have a postero-lateral displacement of the mandible.


Medical ethics: some uses, abuses, and limitations.

A backlash against medical ethics may be developing because of a misunderstanding of its purpose and limitation.  A primary role of medical ethics is to "structure" the disputed issues--i.e., by detailing the relevant principles and implications, analyzing the pivotal concepts, and focusing on the relevant facts.  Medical ethics is limited by being unable to discriminate finely, so that a single line of action can seldom be determined by moral criteria alone.  Underlying many criticisms of medical ethics is the failure to realize that medical ethics as such is not a reform movement or an effort to inspire moral behavior, that it is not and cannot be a specialist's body of esoteric knowledge, that it requires facts and conceptual analyses from other fields to do its work, and that value arguments can be carried farther than one generally expects.


[Morphological changes in lung tissue developing during controlled respiration in patients with severe neurological diseases].

Morphological analysis of lungs was carried out in patients dying in the Department of Neurology who were treated before death by controlled respiration with respirators. Changes in the pulmonary tissue included mainly atelectasis and chronic oedema. For a better analysis the material was divided into 4 groups. Group I included earliest changes with slight atelectasis and hyperaemia of alveolar septa. Group II comprised cased with advanced atelectasis and manifest oedema. Group III contained cases with hyaeline membrane presence. In group IV pulmonary fibrosis was found. These findings were similar to those observed in other patients treated with respirators.


The place of a general intensive care unit in a metropolitan hospital.

The results of a six-year survey are given of the admissions, treatment and prognosis of 3310 patients in the intensive care unit at Middlemore Hospital from 1966-72. The range and extent of the treatment underlines both the need for and the value of a general intensive care unit in the integrated daily routine of a large general hospital.


Anaemia in the elderly: caveat caecum.

The experience of a professorial unit over a four-year period of carcinoma of the colon and rectum is described. The high incidence of anaemia in lesions proximal to the splenic flexure is shown. The distressing misdiagnosis of the cause of this anaemia is pointed out, and the consequent misuse of haematinics in the form of blood transfusion, iron and vitamin B12 is shown.


Environmental lead exposure in Christchurch children: soil lead a potential hazard.

A study of childhood blood lead levels and of soil lead levels has been carried out in Christchurch. The results indicate a potent hazard especially to the child with unusual appetite for soil. Screening and preventative programmes are briefly discussed.


Dural invasion by pituitary tumours.

In 12 cases of pituitary tumour the dura mater of the sella turcica or diaphragma sellae in contact with the tumour was examined histologically. In nine cases tumour cells were found lying deep in the substance of the dura. Dura from the sella of seven subjects without pituitary disease, obtianed at autopsy, showed no inclusions of pituitary tissue. Four of the cases studied were known before death to suffer from an invasive pituitary adenoma. Of eight surviving cases operated upon in the last two years, five showed dural invasion by tumour. The present report suggests that the condition may be more frequent than expected and that with more study it may provide an index of prognosis. It also defines a requirement for the surgeon aiming to prevent recurrence of tumour after operation or to achieve a complete endocrine ablation.


Stevens-Johnson syndrome with hepatitis following therapy with ampicillin and cephalexin.

The Stevens-Johnson syndrome is rarely associated with hepatitis and neither entity is commonly seen following the use of ampicillin or cephalexin. An infant is described in whom both entities appeared simultaneously following therapy with these drugs.


Congenital dislocation of the hip in Southland.

A study of incidence of congenital dislocation of the hip in Southland was undertaken. Covering as it does a 20-year period during which the common age of diagnosis was reduced from 20 months to three months, this series shows a rising recorded incidence of CDH in a period associated with the arrival of a resident orthopaedic surgeon and introduction of the test of limited abduction with x-ray confirmation. The incidence in the succeeding 10 years rising to 2.9 per thousand live births was between the old average for late diagnosis and that obtained with neonatal examination. A higher incidence among winter births, being twice that of summer, agrees with previously published series. An area of higher incidence on the South coast appears to be explained by two families which include seven of the 25 children born in that zone and 12 of the total 103 in the series. In these two families, the affected children are related by being cousins or second cousins.


The transient nephrotic syndrome of pregnancy.

The transient nephrotic syndrome was observed in 24 pregnancies in 23 patients, over a five-year period, in a base hospital obstetric unit. The clinical and biochemical features of this syndrome were similar to the nephrotic syndrome observed in non-pregnant patients. In only half the episodes was the patient a primigravida. In three multigravida patients, previous pregnancies were normal. In 10 of the 24 pregnancies, a perinatal death occurred. A bad fetal prognosis was associated with an early onset of the nephrotic syndrome. Of 11 pregnancies in nine patients occurring after the pregnancy complicated by the transient nephrotic syndrome, seven were normal. One pregnancy was complicated by heavy proteinuria, one by hypertension and intra-uterine death, one by an hydatidiform mole, and one was terminated.


Scombroid-type poisoning induced by the ingestion of smoked kahawai.

Three incidents of presumptive scombroid poisoning were reported in the Wellington area in 1973. Two of these cases were attributed to canned mackerel and the third to smoked kahawai. The marked similarity of the symptoms of the kahawai poisoning to those of the other two outbreaks of scombroid fish poisoning and the relief following anti-histamine therapy suggests that the poisoning arose from a similar source. Analysis of the extracts from the smoked kahawai revealed an abnormally high level of histamine and the presence of an unknown toxin. The unknown substance resembled saurine, the toxin that has been incriminated in scromboid poisoning, thus suggesting that scombroid intoxication may not be confined to fish belonging to the sub-order Scombroidei.


Cyanosis and unrecognised atrial septal defect in children.

Two unusual cases of cyanosis and atrial septal defects are presented. Relative hypoplasia of the right ventricle was an associated feature. In both cases cyanosis was the presenting symptom and the usual clinical signs of atrial septal defect were absent. Chest x-rays and electrocardiograms were normal and the correct diagnosis was not made until after cardiac catherisation.


Late presenting, intrarenal haematoma as a complication of renal biopsy.

An intrarenal haematoma, necessitating surgical evacuation, is described as a novel, late presenting, complication of percutaneous renal biopsy in a patient with amyloid disease.


Christchurch traffic trauma survey: Part 1, Blood alcohol analysis.

Some accurate information concerning the drivers involved in traffic accidents was obtained in a survey at Christchurch Hospital. Investigation of these drivers' occupations revealed that a significant proportion came from the semi-skilled and unskilled occupational groups. Alcohol is confirmed as an important factor in traffic accidents and a number of other characteristics of the drivers are described. The dangers of relying on officially-acquired statistics for research work are revealed.


Non-compliance and errors of drug administration in patients discharged from acute medical wards.

Three hundred and fifteen patients discharged from acute general medical wards over an 18-month period were studied prospectively to determine deficiencies in medication ingestion from that expected by the hospital clinicians. Thirteen percent did not receive an entirely correct written prescription at the time of discharge from hospital. In 4.5 percent this was the sole reason for treatment failure. Excluding these patients, 40.5 percent of the remainder admitted to medication variations over a 1-6 week period. Non-compliance proved to be a cause of drug default by patients three times as frequently as simple error. Where all errors were considered the ratio was 2 : 1. Whereas non-compliance (indicating volitional intent) was a more common basis for medication variation in Europeans, simple error was a more common cause in Polynesians. Two out of every five of the latter group took incorrect or incomplete therapy because of misinterpretation of instructions, either provided by hospital clinical staff, or printed upon their medication containers. The reasons for non-compliance and simple error are elucidated and the problem of non-delivery of expected medication is discussed. In devising methods for improving accuracy of drug self-administration after discharge from hospital the entities of simple error and non-compliance warrant individual attention.


A study of the normal range of blood pressure in the aged New Zealand male.

A study of blood pressure in males 60 years of age and over, its relationship to age, ideal body weight and time of day, was performed by taking a total of 442 recordings on 133 subjects. No relationship between arterial pressure and increasing age was demonstrable. The relationship between arterial pressure and ideal body weight which exists in other sectors of the population also exists in this age group. In this age group, arterial pressure was not found to vary significantly during the day.


Hyperkinesis and chronic constipation.

A series of hyperkinetic children (Minimal Brain Dysfunction) is presented, who in part or whole responded to therapy for chronic constipation.


Streptococcus salivarius, Streptococcus sanguis and Streptococcus "mitis" as indicators of contamination of root canal cultures.

Small samples were taken from the first drop of saliva entering an operation field for root canal treatment isolated by rubber dam, which was intentionally leaky. The samples were primarly cultured in TAS- and BLH-medium and on MS-agar aerobically. The culture media were inoculated directly and via transport medium (VMG III). The cultures were analysed for Strep. salivarius, Strep. sanguis and/or Strep. "mitis" after subculture on MS-agar as soon as visible growth had appeared in the broth media and again after a further 2 days. The following observations were made: 1. Strep. salivarius was almost regularly found in either or both of TAS- and BLH-medium at primary culture of the samples contaminated with saliva. The result was the same whether these broth media were inoculated directly or via VMG III. 2. Strep. salivarius was always found in mixed cultures and was nearly always accompanied by Strep. sanguis and/or Strep. "mitis". 3. Strep. salivarius as well as Strep. sanguis survived two days after visible growth significantly more oftern in BLH-medium than in TAS-medium. The findings lend support to the hypothesis based on clinical studies that when present in root canal cultures Strep. salivarius is ascribable to contamination with saliva.


Denture stomatitis. A histological and microradiographic study of the alveolar mucosa.

The alveolar mucosa in the upper jaw from 12 patients suffering from severe denture stomatitis was examined histologically and microradiographically using ultrasoft X-rays. Pathological changes of the epithelial cell layers were observed in all cases. In 10 of the 12 cases examined no keratinization was found. A reduction in the number of epithelial cell layers was commonly observed. In most cases the connective tissue showed signs of moderate to severe inflammation. The inflammatory reaction and the degenerative changes of the tissue were presumably due to a combined effect of microorganisms and mechanical trauma.


Variation of caries frequency with socio-economic background in unselected and extreme groups of 14-year old children in Malmö.

The purpose of the present investigation was to find out whether any correlation exists between socio-economic factors and caries frequency in unselected and extreme groups of 14-year old school children in Malmö. The material consisted of 360 randomly selected 14-year old school children in Malmö (1969) and their parents. The number of DF-surfaces was obtained from the records of the school dental service. Data on the parents' occupation and gross incomes in 1969 were obtained from the tax office in Amlmö. Extreme groups were obtained by chosen those 10% with the highest caries frequency (H'-group) and a corresponding group with the lowest frequency of caries (L'-group). These two subgroups were compared with a selection of 14-year old school children with high (H-group) and low (L-group) caries frequency, which have been analysed earlier in respect of socio-economic background. No significant correlation was found between socio-economic factors and caries frequency in the non-stratified selection. H'-group and L'-group, on the other hand, showed marked differences in socio-economic background. Compared with the H-group, the H'-group showed a higher number of DF-surfaces. This difference was due to variations in distribution of caries between different schools but was not clearly correlated to socio-economic factors. The differences in socio-economic distribution between H'-group and H-group like between L'-group and L-group were not found to be significant. The findings mean that the conclusions drawn regarding socio-economic factors and dental care regarding H- and L-group also can be regarded as representative of schoolchildren with extremely high and low caries frequency, respectively.


Focal epithelial hyperplasia. Report of five new cases from Argentina.

Five cases of focal epithelial hyperplasia in Argentina from 1968 to 1974 are reported. There was an age range from 11 to 27 years, with an average of 18 years. Three of the patients were born in Jujuy in the northwest corner of the country. Two of these cases were observed in an epidemiologic study carried out among 8,895 20-year-old Argentine men from different areas.


Observation of the articular disc.

This article reports on a 5-year study of 198 articular discs of the human temporomandibular joint. The investigation revealed a striking incidence of disc degeneration, notably bilaterally presented. The classification used to qualify the condition of the discs consisted of maximal and minimal degeneration and normalcy. We sought to establish the "norm" for the disc in each successive decade. The fourth decade revealed no degeneration. Disc alteration follows soon after, as shown by the rather high total curve in the fifth decade. Changes are most marked in the fifth, sixth, and seventh decades. There is inconclusive evidence as to the influence of the dentition on disc alteration. However, the view that a complete and/or partial dentition is least likely to contribute to disc problems seems plausible. In general, no one causal agent could be incriminated with certainty.


The staphylococcal scalded-skin syndrome versus erythema multiforme.

This article reports a case of scalded-skin syndrome in a young child. Characterized by a generalized exfoliative dermatitis resembling scalded skin, the disease may involve the oral mucosa and must be differentiated from Stevens-Johnson syndrome (erythema multiforme). Since the etiology is specific, the disease can be treated with antibiotics with dramatic results.


Solitary intraductal papilloma of the minor salivary glands.

A case of solitary intraductal papilloma of a minor salivary gland is presented. The lesion was diagnosed clinically as a mucocele and has not recurred in 6 months of observation. This case is compared, on the basis of clinical data and histomorphologic findings, to three other known cases. Discussion is made of the role this lesion might play in the etiology of ductal obstruction, and the histologic findings of the intraductal papilloma of minor salivary glands and the solitary intraductal papilloma of the breast are compared.


Benign cementoblastoma (true cementoma).

Benign cementoblastoma is a rare benign odontogenic tumor of mesenchymal origin. As only a few documented cases have been reported in the literature, the clinical and histologic criteria for identifying this type of tumor are still uncertain. Thus, problems of differential diagnosis warrant the present report of a case of benign cementoblastoma in the mandible of a 27-year-old man.


Microradiographic description of a crown dilaceration.

A case of a crown dilaceration in an upper permanent incisor of a 6-year-old child is described. Microradiographs of sagittal sections demonstrated that enamel was broken into fragments which differed on the vestibular and palatal sides. A study of the structural lines in the dentin layer and the disposition of the enamel fragments permits consideration of the lesion as a consolidated fracture.


Lip reconstruction following resection for an unusual basal-cell carcinoma.

Basal-cell carcinoma most commonly occurs in men in the fifth to seventh decades of life. The area of the lesion is usually one that has frequent exposure to the sun: the middle third of the face and upper lip. An unusual case of basal-cell carcinoma occurring on the lower lip and involving the commissure in a 21-year-old woman is presented. The surgical procedures for resection of the tumor and reconstruction of the commissure are described.


Coated versus non-Proplast-coated endosseous blade-vent dental implants.

In order to determine the efficacy of applying Proplast to dental endosseous bladevent implants, this material was coated on half of sixteen such implants which were bilaterally placed in the mandibles of eight rhesus monkeys. No difference in the clinical acceptability could be ascertained between the two groups. Histologic examination revealed a loose connective tissue layer around the noncoated implants which was not evident around the coated ones.


Rhinocerebral mucormycosis: diagnosis and treatment. Report of two cases.

Rhinocerebral mucormycosis (phycomycetes), a human fungal disease with oral and perioral findings, has an extremely high morbidity and mortality. The disease is most frequently seen in patients with poorly controlled diabetes. The symptoms, findings, and treatment of rhinocerebral mucormycosis are discussed, and two case histories are presented.


Fractured condyle in a  3-month-old infant.

A 3-month-old infant sustained trauma to the mandibular symphysis resulting in radiographic evidence of a fracture of the right condylar head. This presented the diffculty of performing a clinical examination and total reliance on history of a trauma and subsequent swelling. Multiple radiographs of the condyles were used to establish the diagnosis and rule out a film artifact. No definitive treatment was required other than muscle exercises and parental instruction as to potential problems.


A sublingual-submandibular calcific mass associated with tumoral calcinosis in a patient with suspected milk-alkali syndrome.

The milk-alkali syndrome is a disorder with diverse clinical and biochemical manifestations. It includes three known clinical syndromes. A case of milk-alkali syndrome with associated tumoral calcinosis is presented. The patient developed an unusual oral mass as part of the disease complex. Treatment consisted of excision of the intraoral mass, diet management, and surgical correction of the associated ulcer disease.


Calcifying odontogenic cyst. A review and analysis of seventy cases.

Six new cases of the calcifying odontogenic cyst are presented. These and sixty-four previously reported cases have been studied to further delineate characteristic clinical, radiographic, and histopathologic features of the calcifying odontogenic cyst. A review of the literature with emphasis on the possible histogenesis of the calcifying odontogenic cyst and the nature of the "ghost cells" and their products is also presented.


Temporomandibular degenerative joint disease. Part I. Anatomy, pathophysiology, and clinical description.

The anatomy and function of the temporomandibular joint (TMJ) are described in the detail needed to evaluate and treat temporomandibular degenerative joint disease (TDJD). Innervation of the joint and the mechanism of arthralgia are described and related to TDJD. The clinical course of TDJD, radiographic evaluation of it, histopathologic description, and etiology are presented.


An unusual case of temporomandibular joint ankylosis.

An unusual cause of ankylosis of the temporomandibular joint is presented. The treatment plan took into account the potential hazards of major vessel hemorrhage and airway obstruction.


Maxillary exostoses. Surgical management of an unusual case.

A case of an unusually large palatal torus and maxillary exostoses is presented. The preoperative evaluation, including laminagrams, is demonstrated. The surgical approach, with an apparent satisfactory result, is also described.


The elfin facies syndrome.

The elfin facies syndrome is characterized by idiopathic infantile hypercalcemia; mental retardation; cardiovascular anomalies, usually supravalvular aortic stenosis and peripheral pulmonary artery stenosis; a peculiar elfin facies and oral anomalies, primarily enamel hypoplasia and oligodontia. The dental features found in the three cases reported include enamel hypoplasia, severe dental decay, oligodontia, pulp stones, microdontia, and abnormally small roots. Some consistent cephalometric abnormalities were thought to contribute to the unusual facial appearance of these patients.


Bacterial endocarditis: a retrospective study.

A retrospective study was done on patients admitted to the University of Michigan Hospital from 1962 to 1972 with a diagnosis of bacterial endocarditis. The findings in the group studied indicate that Streptococcus viridans was the predominant causative organism, males were affected three times as often as females, erythromycin was effective against organisms of oral origin, dental procedures were not definitely established as responsible for the onset of the disease in any of the cases, and rheumatic heart disease and congenital heart disease were the predominant, but not the only, predisposing factors.


Verruciform xanthoma. Further light and electron microscopic studies, with the addition of a third case.

The authors report their third case of verruciform xanthoma confirmed by electron microscopy and frozen-section lipid stains. Studies of the blood in this case revealed normal levels of triglycerides, cholesterol, and glucose, just as in the previous two cases reported. An ultrastructural search for etiologic factors with the use of material from all three cases resulted in the hypothesis that this lesion is initiated within the epithelium. The authors propose that epithelial entrapment with degeneration and accumulation of lipid may be the logical sequence of early events leading to the formation of foam cells.


Juvenile pemphigus vulgaris. Report of a case.

Although pemphigus vulgaris rarely occurs in childhood, we herewith report the history of a 19-year-old patient with an apparent 4-year course of pemphigus. In this patient, as in every previously reported case of childhood pemphigus, oral lesions preceded the appearance of skin manifestations. The importance of early biopsy and adequate treatment with adrenocorticosteroids is emphasized.


Enamel defects associated with tuberous sclerosis. A clinical and scanning-electron-microscope study.

The clinical and scanning-electron-microscope appearances of enamel defects in six patients with tuberous sclerosis are described. The pit-shaped enamel defects seem to be pathognomonic of the disease. The detection may be an important help in the early diagnosis of this complex syndrome.


X-ray production variability.

Some dental x-ray generators do not produce the quantity of x-rays expected at the kilovoltage and milliamperage setting made. A simple experiment was performed on five dental x-ray generators of three manufacturers to test their output in roentgens per minute at a range of kilovoltage and milliamperage settings. Each generator had variable kilovoltage and milliamperage capability. The recorded output was compared with its theoretic output. The results confirm the suspicion that considerable output variations exist and suggest a serious problem to the practitioner wishing to expand his radiographic technique armementarium.


Relations between tooth positions and focal troughs of panoramic machines.

A comparison of the established focal troughs of three panoramic machines with positions of the teeth in the dental arches of 240 patients. The patients, divided into twelve cells, were selected on the basis of race, sex, age, number of teeth, and occlusion. Occlusal registrations were made in fast-set acrylic. Tooth centers were identified and, with the midline-incisal point as a reference point, various composite drawings of tooth positions of patients were made. The total composite of all teeth revealed the striking similarity of the arches. Superimposition on the focal troughs showed that the focal trough of the Panorex easily encompassed all tooth positions. The focal trough of the Orthopantomograph encompassed all tooth positions, although tooth centers lie on the edges of the trough. The focal trough of the GE-3000 with profile index 10 extended so far buccally that many teeth are positioned lingual to the trough. The focal trough of the GE-3000, when reduced uniformly to profile index 7.5, encompasses all tooth positions although some positions fall quite near the borders of the trough.


Nucleotide composition analysis of tRNA from leukemia patient cell samples and human cell lines.

A technique developed for analysis of less than microgram quantities of tRNA has been applied to the study of human leukemia. Leucocytes from peripheal blood and bone marrow samples of six, untreated leukemia patients and cells of five different established human cell lines were maintained for 18 hours in media containing (32P)-phosphate. Incorporation of radioactive phosphate into the cells from the patient samples was slightly less than that of the cell lines. Likewise, incorporation of (32P)-phosphate into the tRNA of the patient samples (approximately 5 x 106 DPM/mug tRNA) was also less then that incorporated into the tRNA of the cell lines. The major and minor nucleotide compositions of the unfractionated tRNA preparations from each patient sample and each cell line were determined and compared. Similarities and differences in the major and minor nucleotide compositions of the tRNA preparations are discussed with reference to types of leukemia and the importance of patient sample analysis versus analysis of cultured human cells.


Amino-acid sequence of bovine carboxypeptidase B.

The amino-acid sequence of bovine carboxypeptidase B [peptidyl-L-lysine(-L-arginine)hydrolase, EC 3.4.12.3] has been determined using the heavy and light chains of the enzyme isolated from spontaneously activated pancreatic juice. Comparison of the sequence with that of carboxypeptidase A shows that the two enzymes are homologous (49% identity) and that all but one of the functional residues identified in carboxypeptidase A occur in corresponding loci in carboxypeptidase B (peptidyl-L-amino acid hydrolase, EC 3.4.12.2). The exception is the replacement of Ile-255 at the bottom of the substrate binding pocket of carboxypeptidase A, by aspartic acid in carboxypeptidase B. This single change can account for the difference in specificity of the two enzymes.


Stereochemistry of decarboxylation of trans-4-hydroxycinnamic acid by Aerobacter.

The stereochemistry of the decarboxylation of trans-p-coumaric acid to 4-hydroxystyrene by Aerobacter aerogenes has been examined. The decarboxylation has been found to proceed with retention of the geometry about the trans-substituted double-bond.


Remark on the phase problem in crystallography.

The ambiguities found in determining a crystal structure from x-ray diffraction can be resolved if one takes into account the random thermal motion of the atoms.


South American mammal zoogeography: evidence from convergent evolution in desert rodents.

Current theories regarding colonization of South America by mammals are divided between those supported by fossil evidence, which suggest the original mammal fauna of the isolated continent was augmented by early immigrants (primates, caviomorph rodents, and later, procyonids) with a final large influx of northern mammals occurring with the formation of the Panama land bridge, and an opposing view which states that the purported "recent invaders" are too taxonomically and ecologically differentiated to have colonized since the land bridge arose. The second theory suggests that most extant mammals entered before the Plio-Pleistocene land connection. An analysis of degree of physiological adaptation, natural history, distribution patterns, and a multivariate assessment of convergent evolution of Monte Desert rodents indicate that South American cricetine rodents are not highly specialized for desert life. Their degree of adaptation could be accounted for, in large part, by adaptations for arid or semiarid Andean habitats. No Monte Desert rodent has developed the specialized desert traits that have evolved in most desert rodent faunas of the world, although extinct marsupials similar to living bipedal desert rodents were present in the Monte as recently as late Pliocene. Evidence suggests that Monte caviomorphs have been associated with the desert for a longer period than cricetines, and that the latter represent a fairly recent invasion of the Monte Desert. The data thus support the first hypothesis of South American mammal colonization.


Activation of adenylate cyclase by phosphoramidate and phosphonate analogs of GTP: possible role of covalent enzyme-substrate intermediates in the mechanism of hormonal activation.

Incubation of rat fat pad membranes with 5-guanylyliminodiphosphonate [Gpp-(NH)p] and 5-guanylylmethylenediphosphonate [Gpp(CH2)p], but not GTP (with or without hormones), at 24 degrees or 30 degrees (but not at 4 degrees) greatly stimulates adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] measured after thoroughly washing the membranes. The rate of activation is relatively slow, even with very high (and saturating) concentrations of the analogs. Binding alone appears to be insufficient for activation. Hormones (catecholamines, glucagon) increase the rate but not the extent of activation, even when saturating analog concentrations are used. The dependence on analog concentration (apparent Km) varies with the time of incubation. GTP and very high concentrations of ATP inhibit the activation by Gpp(NH)p, but this effect is dependent on the length of incubation and can be overcome with time. The activated state is not reversed upon incubation of the washed membranes at 30 degrees, even in the presence of GTP, or by solubilization with nonionic detergents. Also, Gpp(NH)p can directly stimulate the control, solubilized enzyme. The activated state of the solubilized enzyme persists upon specific adsorption to and subsequent elution from an organomercurial-agarose column. It is suggested that after forming reversible Michaelis complexes of relatively low affinity, these analogs may react irreversibly with the GTP regulatory site of the enzyme, perhaps forming p(NH)p- and p(CH2)p-covalent enzyme intermediates which capture the activated state of the enzyme. GTP, after binding, may normally activate the enzyme by forming a "labile" pyrophosphoryl enzyme intermediate, and hormone receptors may function to increase the rate of formation (and thus concentration) of this active state of the enzyme.


Molecular model of postsynaptic potential.

A molecular model of the excitatory postsynaptic membrane is given in terms of two biochemical cycles intimately associated: an acetylcholine cycle and a calcium cycle. The acetylcholine controls the Na ionophores while calcium ions control the tk ionophore. The two ionophores are spatially separated but interact in such a way that the variation in K conductance precedes that in Na conductance. Digital simulation shows that our model accounts quantitatively for both the evolution of excitatory postsynaptic potential and current in a variety of experimental conditions.


Visualization of actin fibers associated with the cell membrane in amoebae of Dictyostelium discoideum.

Amoebae of Dictyostelium discoideum were attached to a surface coated with polylysine, and the upper portion of the cells was sheared off with a stream of buffer. Scanning and transmission electron microscopy showed that the cytoplasmic surface of the exposed membrane was covered with fibers consisting of actin-containing filaments. The actin was identified by its solubility properties and its ability to interact with muscle myosin.


Cooperative activation of action potential Na+ ionophore by neurotoxins.

Four neurotoxins that activate the action potential Na+ ionophore of electrically excitable neuroblastoma cells interact with two distinct classes of sites, one specific for the alkaloids veratridine, batrachotoxin, and aconitine, and the second specific for scorpion toxin. Positive heterotropic cooperativity is observed between toxins bound at these two classes of sites. Tetrodotoxin is a noncompetitive inhibitor of activation by each of these toxins (KI = 4-8 nM). These results suggest the existence of three functionally separable components of the action potential Na+ ionophore: two regulatroy components, which bind activating neurotoxins and interact allosterically in controlling the activity of a third ion-transport component, which binds tetrodotoxin.


Transfer of the human gene for hypoxanthine-guanine phosphoribosyltransferase via isolated human metaphase chromosomes into mouse L-cells.

We have transferred the human gene for hypoxanthine-guanine phosphoribosyltransferase (HPRT, EC 2.4.2.8; IMP:pyrophosphate phosphoribosyltransferease) via isolated metaphase chromosomes from human HeLa S3 cells into murine A9 cells which lack functional murine HPRT activity, using the technique of McBride and Ozer (Proc, Nat. Acad. Sci. USA 70, 1258-1262, 1973). Three transformed clones were isolated which contained human HPRT activity as determined by electrophoretic and immunochemical assays. Twenty human isozymes other than HPRT whose genes have been assigned to 14 human chromosomes were found to be absent in our transformed clones. Moreover, the human isozymes of hlucose-6-phosphate dehydrogenase (EC 1.1.1.49; D-glucose 6-phosphate:NADP 1-oxidoreductase) and phosphoglycerate kinase (EC 2.7.2.3;ATP:3-phospho-D-glycerate 1-phosphotransferase), whose genes have been linked with the HPRT gene to the long are of the human X chromosome, were also absent. On the basis of the known linkage relationships of the three markers, we thereby suggest that the transferred piece of human genetic material is smaller than 20% of the human X chromosome or less than 1% of the human genome. This estimate assumes a normal syntenic relationship for the long arm of the X chromosome in HeLa S3 cells. In agreement with this conclusion, no human chromosomes could be detected in our transformed clones. When grown under nonselective conditions about 3% of the gene transfer cells lost the human HPRT marker per cell generation. Transformants that had lost human HPRT activity were subjected to hypoxanthine-aminopterin-thymidine selection. The frequency of revertants to the HPRT(+) phenotype was less than 1 x 10(-6), and two revertants that were obtained possessed the mouse electrophoretic phenotype. These results argue against a stable integration of the human donor genetic material into the mouse recipient genome.


Distribution of end-to-end distances of oligopeptides in solution as estimated by energy transfer.

A homologous series of oligopeptides each containing at its ends a donor and an acceptor of electronic excitation energy was synthesized by the solid-phase method. N-5-(2-Hydroxyethyl)-L-glutamine was the repeating unit, and peptides containing 4, 5, 6, 7, 8, and 9 of these amino-acid residues were prepared. The chromophores naphthalene and dansyl, which were used as donor and acceptor, respectively, fulfil the conditions necessary for energy transfer according to the Förster mechanism. A distance corresponding to 50% efficiency of energy transfer, tro = 22 plus or minus 1 A, was calculated. The kinetics of fluorescence decay of an oligomer containing the naphthalene chromophore only could be described precisely by a monoexponential function. In contrast, the kinetics of the decay curves of the fluorescence of the donor of all of the oligomers containing both donor and acceptor, as measured in viscous solution, deviated markedly from monoexponential behavior. The deviation was interpreted in terms of the great number of different conformations that the various molecules of each of the oligomers attain in solution, leading to characteristic end-to-end distribution functions between the donor and acceptor. Numerical adjustment of the parameters of some of the previously proposed expressions to describe the end-to-end distribution enabled the reconstruction of the kinetics of the fluorescence decay of the donor with great precision. The end-to-end distribution functions for the various oligopeptides were thus evaluated.


Use of biochemical lesions for selection of human cells with hybrid cytoplasms.

Techniques for preparing large populations of anucleate cytoplasms from cultured eukaryotic cells have only recently been described. The principal value of anucleate cytoplasms derives from studies that can be done after they are fused to whole cells. Since present methods for the isolation of heterokaryons are unsuitable for the selection of hybrids between whole cells and anucleate cytoplasms (heteroplasmons), a selective system has been developed which is based on the capacity of anucleate cytoplasms containing active enzymes to rescue whole cells poisoned with iodoacetate. Ethidium bromide, a partially effective agent, was used in conjunction with iodoacetate to demonstrate the feasibility of selecting heterokaryons by producing complementary biochemical lesions in the parental cell strains. The potential for artifact in these systems is not, however, entirely precluded.


Scanning transmission ion microscope with a field ion source.

Experiments with a low-resolution scanning transmission ion microscope, using hydrogen ions from a field ionization source, indicate that it will be feasible by this approach to aim at high-resolution ion microscopy. Micrographs of unstained biological specimens have been obtained by critical range absorption of a 55 keV hydrogen ion beam at a resolution of 2000 A.


Subversion of immune system by tumor cells and role of prostaglandins.

Mice bearing syngeneic tumors, chemical and virus-induced, became immunologically unresponsive to sheep erythrocytes. The increase in the degree of unresponsiveness with tumor growth suggested a causal relationship. Immunosuppression was in fact caused by the tumor cells because the addition of tumor cells to in vitro cultures of spleen cells and sheep erythrocytes resulted in suppression of antibody response. Suppression was dose dependent with a ratio of 1 to 1000 of tumor cells to spleen cells sufficient to produce significant suppression. Prostaglandins were found to have a role in immunosuppression by tumor cells in that PGE2 was itself immunosuppressive and in that indomethacin and aspirin, inhibitors of prostaglandin synthetases, blocked immunosuppression in vitro and retarded tumor growth in vivo. These findings suggest that tumors, although antigenic, may be able to escape immuno-sureillance by their host by means of subverting the immune system. Thus, success of immunotherapy may well depend on our ability to prevent or block the immunosuppressive activity of tumors.


A protein factor essential for microtubule assembly.

A heat stable protein essentail for microtubule assembly has been isolated. This protein, which we designate tau (tau), is present in association with tubulin purified from porcine brain by repeated cycles of polymerization. Tau is separated from tubulin by ion exchange chromatography on phosphocellulose. In the absence of tau, tubulin exists entirely as a 6S dimer of two polypeptide chains (alpha and beta tubulin) with a molecular weight of 120,000, which will not assemble into microtubules in vitro. Addition of tau completely restores tubule-forming capacity. Under nonpolymerizing conditions, tau converts 6S dimers to 36S rings-structures which have been implicated as intermediates in tubule formation. Hence, tau appears to act on the 6S tubulin dimer, activating it for polymerization. The unique ability of tau to restore the normal features of in vitro microtubule assembly makes it likely that tau is a major regulator of microtubule formation in cells.


Induction of endogenous and of spleen focus-forming viruses during dimethylsulfoxide-induced differentiation of mouse erythroleukemia cells transformed by spleen focus-forming virus.

Spleen focus-forming virus-transformed erythroleukemic cell clones, which have been established by infection of N type mice with NB trophic Friend virus, continue to release biologically active tfriend virus of NB host range. Dimethylsulfoxide induces erythroid differentiation and a 10- to 100-fold increase in the release of biologically active Friend virus. The increase of Friend virus release is a function of the differentiating erythroleukemic cell. The induced Friend viurs is not the NB tropic Friend virus complex, but shows N host range. The induction of the Friend virus complex is due to simultaneous induction of both spleen focus-forming and endogenous viruses.


Identification of human RNA transcripts among heterogeneous nuclear RNA from man-mouse somatic cell hybrids.

In man-mouse hybrid line from our cell library, the only cytological detectable portion of the human genome is the X chromosome, and the only genetic markers regularly expressed are coded by genes known to be ?X-linked. A component of the heterogeneous nuclear RNA of these cells was found to be complementary to repetitive human DNA sequences by means of RNA-DNA hybridization on nitrocellulose filters. The same procedure also permitted the identification of hybrid cell DNA sequences that are complementary to human heterogeneous nuclear RNA. This experimental approach, coupled with hybridization studies in situ, is expected to yield critical data on the distribution and the specificity of the repetitive DNA sequences present in the human genome and to provide a new tool for cytological mapping of human chromosomes.


Play: early and eternal.

A systematic 12-week investigation of development of play behavior was conducted with eight socially reared rhesus monkey infants. A new, basic and primary play form termed self-motion play or peragration was identified and examined. This behavior follows a human model which includes a wide range of pleasurable activities involving motion of the body through space, e.g., rocking, swinging, running, leaping, and water or snow skiing. It can be argued that self-motion play is the initial primate play form and because of its persistence constitutes a reinforcing agent for maintaining many complex patterns and even pastimes. Monkey self-motion play in the present study was divided into five separate patterns in order to compare the relative importance of social and individual peragration play, the role of apparatus and the overall developmental relationships between the different individual and social self-motion play patterns. The data showed that from 90 to 180 days of age self-motion play was independent of other forms of play, that individual self-motion play appeared earlier and with significantly greater increases in frequency than did social self-motion play, and that apparatus was a necessary component for significant increases in social self-motion play. Other findings were that self-motion play existed independent of locomotion and, though initiated by exploration, was separate from it. Therapeutic implications of self-motion play were discussed.


Secretion of a nerve growth factor by mouse neuroblastoma cells in culture.

Analyses of supernatant solutions from mouse C1300 neuroblastoma cultures by two independent immunoassays reveal that these cells secrete a factor which is immunochemically similar to mouse submaxillary gland nerve growth factor. The neuroblastoma factor is also biologically active in inducing neurite outgrowth from embryonic sensory ganglia-an effect that is completely blocked by specific antibody to nerve growth factor. Neuroblastoma cells are known to be functionally responsive to nerve growth factor, and the observation that they secrete a molecule like it may mean that these cells require or utilize the factor during growth in culture.


Methylated, blocked 5 termini in HeLa cell mRNA.

Poly(A)-containing HeLa cell mRNA prepared from cells labeled with [methyl-(3)H]methionine or [(32)P]phosphate was found to contain a variety of methylated, blocked 5'-terminal structures of two general types: m(7)GpppN(7)-Np and m(7)GpppN(m)-N(m)-Np. In addition, about one-third of the [(3)H]methyl label was present in the N(6)-methyladenosine; this labeled nucleoside was not found in the 3'-terminal one-third of the mRNA chain and thus may also be in the 5' portion of the mRNA.


A co-evolution theory of the genetic code.

The theory is proposed that the structure of the genetic code was determined by the sequence of evolutionary emergence of new amino acids within the primordial biochemical system.


Modulation of lymphocyte mitogenesis.

Comparisons of the stimulation of normal lymphocytes and lymphoma cells by tetrameric concanavalin a (Con ta) and dimeric succinyl-Con A suggest that both stimulatory and inhibitory signals operate to modulate mitogenesis. Synergistic effects can be obtained for the stimulatory event using lectins, phorbol esters, and calcium ionophores, all of which are independently mitogenic for lymphocytes. The inhibitory effects of high doses of Con A could be mimicked by the simultaneous addition of the phorbol ester and Con A under conditions in which both reagents are optimally mitogenic when used alone. No inhibition of stimulation was found, however, when succinyl-Con A was used with phorbol ester under the same conditions. Moreover, when lymphocytes were cultured with Con A in the presence of succinyl-Con A, the inhibitory effect of the native lectin was seen at lower doses than in the absence of the derivative. These observations suggest that the stimulatory and inhibitory portions of the dose-response curve can be manipulated independently and may be mediated by two distinct signals. It is likely the signal for the inhibition of cell proliferation is regulated by the same cell surface modulating assembly that controls the mobility of cell surface receptors.


Catecholamine-induced subsensitivity of adenylate cyclase associated with loss of beta-adrenergic receptor binding sites.

Injection of frogs with beta-adrenergic catecholamines for 1-24 hr produces marked subsensitivity of the erythrocyte membrane adenylate cyclase [ATP pyrophosphate-lyase (cyclizing); EC 4.6.1.1.] to in vitro stimulation by isoproterenol. The subsensitization is specific for catecholamine stimulation, since basal and fluoride-stimulated enzyme activity are unaffected. Maximum isoproterenol-stimulated adenylate cyclase activity declines by 75% in the isoproterenol-treated animals (P less than 0.001). The concentration of isoproterenol causing one-half maximal activation of adenylate cyclase, however, is unaltered. (-)[3H]Alprenolol, a potent competitive beta-adrenergic antagonist, was used to study directly the beta-adrenergic receptor binding sites in the erythrocyte membranes from control and subsensitized animals. A highly significant (P less than 0.005) 60% fall in the number of the beta-adrenergic receptor binding sites ("specific"(-)[3H]alprenolol binding sites) in the treated animals was found. The binding affinity of the sites was not markedly altered. These data suggest that beta-adrenergic catecholamines are able to regulate catecholamine sensitivity of tissues in vivo, by regulating the properties of the beta-adrenergic receptor binding sites.


Radioimmunoassay for melatonin.

Rabbits immunized with human albumin conjugates of N-(p-chlorobenzoyl)-2-methyl-5-methoxyindole-3-acetic acid (indomethacin), 5-methoxytryptamine, and 2-methyl-5-methoxyindole-3-acetic acid produced antibodies that bound [3-H] melatonin. The serologic specificities for the binding of melatonin with antibodies from four antisera to these three immunogens were determined. Melatonin was measurable even at the 0.1 picomole level by a radioimmunoassay. Serotonin, N-acetylserotonin, 5-methoxytryptophol, 5-methoxytryptamine and 6-hydroxymelatonin can be ruled out as immunoreactive material with the use of the multiple antisera of different specificities.


[Statistical analysis of 92 orthodontic cases].

A comparison has been made within 92 children who were either observed or treated by extractions or by orthodontic  appliances and submitted to statistical analysis. Conventional treatments do not influence the skeletal structures except for the convex faces which are favorably modified by plate. The changes of the dental axis varied according to the dental group. The growth direction of the anterior facial structures seems to be constant amongst all considered children.


[Psychological approach to the child in a hospital stomatology department].

The authors describe what form the psychological approach to children by the stomatologist should take. If the future dental care of a patient depends upon the way in which he has been treated at the time of the first consultation, it is obvious that respect and interest for the child should form part of operative technique--just as important as technical skill and aptitude.


[Mesiodistal inclination of permanent 2d molars Angles of bite].

Measurement of the angles formed by the axes of the second permanent molars on the plane of bite in premolar sector was carried out by profile teleradiographies of 50 young adults. These patients showed no abnormality likely to affect the molar alveolar processes in the saggital plane. The results were as follows: Open angle in front of the second upper molar with plane of bite:80degres. Open angle in front of the second lowermolar with plane of bite: 110degrees. Angle of bite of the second molars: 170degrees, identical with the angle of bite of the first molars.


[Semiologic significance of Angle's classifications].

Study of profile teleradiographies and the inclination of the molars in relation to the lateral occlusal plane, make it possible to distinguish various types of Angle's classification: 1. those associated with displacement, 2. those resulting from dento-maxillary disharmony, 3. those resulting from a dento-dental or temporary disharmony, 4. those connected with abnormality of the occlusal path. Examination of the contact of the arches is not then sufficient to establish a diagnosis.


[Induction alveolectomies and root malformations].

In connection with 2 cases of dental retention due to radicular malformations, the authors draw attention to the following three points: 1. The diastema in which the retained tooth develops should exceed its mediodistal diameter. 2. The malformation of the root is not a counter-indication for induction alveolectomy: this triggers growth of the alveolar bone satellite of the tooth, following a process different from the usual mechanism of dental eruption. It could mean that the coronary portion, which is of epithelial origin, is rejected by its bony, connective tissue environment. 3. They would like diagnosis of dento-maxillary disharmony to be graded: --difficult to judge from X-rays alone; --dubious when abnormalities in the transverse diameter of the arches also contribute to crowding of the teeth.


[Calcified parotiditis].

Six cases of parotiditis with multiple concretions clearly seen on X-rays in front view and without contrast, and associated with parenchymatous cavitation, have led us to suggest the concept of calcified parotiditis. The process was seen to be bilateral each time such an eventuality was sought. Histological examination confirmed that the calcifications were situated in the small efferent canals and provides evidence in favour of the similarity between such forms of parotiditis and calcified pancreatitis. As with pancreatitis, it is difficult to say whether such calcifications are responsible for ascending infection or if they result from it.


[Is it possible to make a diagnosis on only the morphological appearance in a child? Importance of complementary examinations in dentofacial orthopedics].

Orthodontic diagnosis cannot be made from the morphological appearance of the patient alone. The skeleton cannot be seen except by radiography. And the positioning of the dental system within the cranio-facial mass depends on the caprice of the musculature which may even simulate displacement of mandible in connection to maxillae. It is to illustrate this fact that we have selected from the Orthodontic Dept. of the Institute of Stomatology the cases of 3 children presenting with an abnormality in incisal contact, characterized by vestibular occlusion of the lower incisors clinically reminiscent of mandibular prognathism. In all of them we found evidence of abnormalities in neuro-muscular behaviour, at rest and in action, whilst teleradiography showed only one case with sagittal displacement of the maxillae, with a Coutand guide mark 9 mm below the bissector.


[Diffuse papulous histiocytosis X of the buccal mucosa during prolonged development of multiple eosinophilic granulomas of the jaws].

A diffuse papulo-erosive histiocytosis of the oral mucosa occurred during the fourth year of progression of a case of multiple maxillary eosinophilic granuloma whilst the bone lesions were progressing favourably. This mucosal form appeared to have completed its course in approximately one year, i.e. much more quickly than each of the bony lesions.


[Multiple cysts of the jaws: basocellular nevomatosis].

The authors presents two cases of basocellular nevomatosis with multiple maxillary cysts. He thought it important to point out the presence of a cyst in the left styloid apophysis, as up to now, epidermoid cysts have never been observed in other facial bones apart from the maxillae in BCN. In conclusion, the author presents three casses, which although showing multiple cysts or pseudocysts of the maxillae, do not belong to the BCN syndrome.


[Lipoma of the buccal cavity apropos of a case of intrajugal lipoma].

Lipoma of the oral cavity is a rare condition. It is a symptomless and slowgrowing tumour. Surgery is the adequate treatment. No recurrence does occur. The author describes a case of lipoma which developped in the cheek.


[Leontiasis ossea: a symptom...!].

The keyword "leontiasis ossea" has no diagnostic significance. It is only a description of a symptom of bone disease with a broad variability such as Paget's disease, fibrous dysplasia, hyperparathyroïdism and condensing osteopathies. (Pyle's disease, or cranio-diaphyseal dysplasia.) The first case presented shows advanced Paget's disease with radiographic signs of maxillary bone pathology. A tooth extraction in this patient was complicated by a severe healing problem. Sequestration occurred after two years. Healing was only obtained after removal of the sequestrum. The authors believe that the healing problem was directly related to Paget's disease of maxillary bone. The second case represents a patient with hyperparathyroïdism, showing an unusual facial swelling as only physical symptom of the disease. The problem of interpretation of biopsymaterial and the occurrence of osteosclerotic appearence on X-ray are discussed. The authors suggest that a complete examination (X-ray of the skeleton, blood and urine parameters, and functionel tests) should be performed to put forward a right diagnosis in the patient, presenting leontiasis ossea.


[Temporomandibular menisci].

The temporo-mandibular meniscus is an anatomical structure which has been the subject of very little recent research. The usual macroscopic and dynamic tests were actually carried out on anatomical specimens taken from injected corpses whose anatomical structures were discoloured, stiff, hardened and unrecognizable, or from meniscectomy for pathological meniscus. In order to approximate as nearly as possible to the actual conditions under which anatomical testing is carried out, we dissected and removed 50 temporo-mandibular meniscuses from fresh corpses (14 females, 11 males between the ages of 42 and 78). Here are the partial conclusions from the macroscopic, microscopic and mechanical study of these 50 meniscuses caried out by us.


[Functional treatment of fractures of the mandibular condyle and its neck].

The functional treatment of condylar and sub-condylar fractures requires very early mobilisation of the mandible, in protraction. This form of treatment, suggested in France since 1928 by L. Lebourg, is usually carried out with the aid of traction using a plaster helmet. The authors use more simple inter-maxillary traction (as parallel as possible from the standpoint of occlusion) followed by propulsion plates.


Haemolytic anaemia with hereditary pyruvate kinase instability developing acute leukaemia.

The case of a 27-year-old woman with pancytopenia, revealing acute monocytic leukaemia and haemolytic anaemia, is described in detail. The underlying cause for the red cell destruction was found to be a pyruvate kinase (PK) instability. Further investigation into three generations of her family (n = 12) disclosed a hereditary PK instability. This was proven by performing biochemical studies to elucidate mutants representing a structurally defective enzyme. Since conversions of pancytopenia with acquired red cell enzyme deficiency into leukaemia have been described, our observation emphasizes that hereditary red cell enzymopathy might also be associated with adult acute leukaemia.


Quantitative determination of splenic red blood cell destruction in patients with splenomegaly.

In order to evaluate a method permitting quantitation of splenic red blood cell destruction, a model of erythrocyte destruction in enlarged spleens was created: Erythrocytes are destroyed in the splenic erythrocyte pool at a constant rate, producing in labelling studies hyperhaemolysis due to random destruction. A mathematical analysis of the model shows that the splenic destruction rate can be calculated with great accuracy from quantitation of the initial excess radioactivity, measured over the spleen during the first days after infusion of 51-Cr-labelled autologous erythrocytes. 18 patients with splenomegaly (479-4700 g) were investigated. The splenic erythrocyte destruction rate was estimated to be between 0.5-4.4% of the total erythrocyte mass per day, increasing significantly with increasing splenic weight. The results indicate that erythrocyte destruction takes place almost exclusively in the enlarged spleen in cases of predominant splenomegaly without complicating immunohaemolysis.


Chromosome abnormalities identified by banding technique in a patient with acute myeloid leukaemia complicating Hodgkin's disease.

Chromosome analyses using the Giemsa banding technique were performed on bone marrow cells in a patient with the association of Hodgkin's disease and acute myeloid leukaemia. All cells had an abnormal karyotype showing an extra chromosome No. 14, loss of one chromosome No. 17 and gain of one chromosome No. 18. These abnormalities are in many respects similar to the karyotype changes of lymphoid cells in malignant lymphomas, suggesting a pathogenetic relationship between the two disorders.


[Odontogenic keratocysts].

Keratocysts may develop from cellular multiplication, from recidivating growth of epithelial cells left after curettage, and they have an important potential growth, they can degenerate into malignancies. There are several etiological possibilities: tissues connected with crown formation, invagination of nucous epithelium, degeneration of follicular cysts producing keratin. The most important characteristic of these cysts is the frequent recidivation. Fron a clinical standpoint, they are classified as benign tumors. After enucleation, the walls of healthy tissue should be reduced, particularly in locations where the access of curettes is difficult. If necessary, apicetomy is performed in order to completely eliminate the cyst walls. Histological examination is mandatory. Finally, radiologic controls during at least six years should be made.


[Prophylactic measures in general dental practice. An inquirly on their state and frequency].

Questionnaires concerning the type of oral examinations and preventive measures used in private practice were sent to 500 randomly selected dentists in the german-speaking part of Switzerland. 300 were returned completed, the majority of these anonymously. In the examination of new patients, bite-wing radiographs were the most commonly used diagnostic aid. This was reported in 60% of the offices--more often by younger than by older pracitioners, more frequently in urban than in rural offices and more often in surgeries treating less than 12 patients a day. Concerning oral restauration itself, the most frequently frequently reported procedures were the treatment of clinically visible carious lesions, polishing and the replacement of defective fillings. A broad spectrum of prophylactic oral hygiene aids were reported. Toothbrush and dental floss combined with oral hygiene instruction, however, were still the most commonly used. There was considerably correlation between the type of prophylactic acids used and the type of the dental practice. According to the questionnaires, fluoride prophylaxis is very regulary carried out and recommended. The ways in which this fluoride prophylaxis is carried out differs from practice to practice. Nutritional prophylaxis counseling was considered in the majority of the offices irrespective of the type of office. Relatively little emphasis was placed upon cooperation of the patient. From the questionnaries we calculated a need for about 550 DH for Switzerland. Younger dentists mentioned this need relatively moe often than older practitioners. A recall system was used in 70% of the practices, whereby annual and semi-annual intervals were reported with equal frequency. It is obvious that the emphasis placed upon prevention is not the same in all practices. This statement is valid also for the carious and periodontal diagnostic measures utilized. Much work as well as maybe a certain resignation resulting from previous failures may prevent the dentist from instituting more preventive measures in his practice. It is obvious that the graduates of the new dental hygiene school can help in this regard. However, because as yet these new graduates cannot supply even one half of the 550 required hygienists, it is discussed whether or not dental chair-side assistants with special training could motivate our patients toward a more satisfactory oral hygiene.


[A new method for intraoral photography: the oral-zoom-converter].

The article describes the design and application of a lens-converter specifically developed for intraoral photography: the Oral-Zoom-Converter. With a few simple manipulations this converter modifies an existing standard single-lens-reflex camera with an electronic flash unit into a compact intraoral setup which delivers excellent photographic results. A special optical mechanism allows for the continuous change of the magnification range between the overview range (lower half of the face) and the closeup range (2-4 crowns of teeth). The revolving friction-lock flash show positions the flash window on the appropriate side of the master lens for optimal illumination of the object. The cost of this converter will be moderate.


[Root fragments of deciduous teeth remaining in the alveolar bone. Microradiographic and ultrastructural study].

Deciduous tooth fragments retained in the alveolar bone can be either unresorbed portions of root, or root splinters of various sizes resulting from a fracture. The composition and ultrastructure of the fragment dentine remain unchanged even after a long period of inclusion; any specific alterations present at the time of inclusion persist. Some fracture surfaces and resorption lacunae of completely embedded fragments are covered with newly-formed cementum, usually in continuity with the preexisting cementum. Osteo-dentinal ankylosis occurs on certain resorption surfaces. The ultrastructure of the ankylosis zones is characterized by the continuity of the collagenous fibrillar framework of the dentine and that of the newly-formed bone, and by the penetration of bone substance into the dentinal tubuli and the pulp canals.


[Prospective evaluation of the risk of hemorrhage. Measures for the prevention of postoperative bleeding in dental surgical procedures].

The authors concern themselves with the problem of a possible prospective hemorrhage. The history of the patients proved to be the most efficient means to prophylaxis: From 250 patients, seven had histories of hemorrhages, mainly after tooth extractions. In the most prominent case, hematologic examination showed a hemophilia A, which was unknown to the patient. Examination of the family uncovered another case of this disease. Two cases could be interpreted as caused by medication. Preopertive selection uncovered only one patient with abnormal Quick value. Practical instruction for pre-, intra-, and postoperative prophylaxis against bleeding may contribute to reduce unexpected and life endangering hemorrhages to minimum.


Hypocalcemia in leukemia.

Hypocalcemia is seen in patients with leukemia and is usually due to renal impairment or to low serum albumin concentrations. Four patients are reported who had hypocalcemia but without these usual explanations. One patient had chronic lymphatic leukemia and overwhelming infections which led to death. The other three patients had chronic myelogenous leukemia in an accelerated phase of the disease characterized by increasing blast cells in circulation, massive hepatosplenomegaly, and myelofibrosis. The cause of the hypocclcemia is unknown.


Angiography in the management of musculoskeletal tumors.

The contribution to pretreatment evaluation and surgical planning of 200 angiograms of bone and soft tissue lesions, mostly tumors, was evaluated. Their accuracy was studied  by careful post-operative examination of gross surgical specimens and histologic sections. The angiograms were helpful in delineating the anatomic extent of lesions and, therefore, in planning the appropriate resection or amputation. This was particularly true in lesions treatable by radical local resection, such as most malignant tumors of soft tissues, giant cell tumors of bone, parosteal osteosarcomas, chondrosarcomas and occasional small central osteosarcomas. The angiograms were of some help in confirming or detecting residual or recurrent tumor and prior resection. This was not true immediately after inadequate local resections because residual tumor was likely to be quite small and reactive vascularity secondary to operation was confusing. Angiography was not accurate or helpful in distinguishing benign from malignant lesions when the clinical presentation and roentgenographic findings were confusing. The surgeon relied on biopsy rather than angiography. Aso, although we saw lymph node blushes on several angiograms, we could not reliably interpret whether or not this represented tumor metastasis. The vascularity of pathologic fractures was also confusing. Pelvic angiograms were difficult to interpret because of the complex anatomy. We made most of our serious mistakes in delineating tumor extent in pelvic lesions. Angiography is valuable in planning operative treatment of tumors if radical local resection is considered or if physical examination and roentgenographic findings do not indicate the appropriate level of amputation.


Mother cell of megakaryocyte.

It was attempted to describe the morphology of the most immature cell of megakaryocytic series. The megakaryocytes were observed with the electron microscope in five cases, being traced back to their immature forms. In two cases the most immature cells of megakaryocytic series were considered to be the cells which were probably identified as lymphocytes under the light microscope, but they were not lymphocytes with the electron microscope. In other two cases it was presumed that neutrophilic and megakaryocytic series were derived from morphologically similar immature cells, since the most immature cells of neutrophilic and megakaryocytic series were not distinguished when they were traced back to their immature forms. These findings suggest that mother cells of megakaryocytes in the adult bone marrow may be identified as lymphoid cells with the light microscope.


Mechanism of platelet liberation.

Megakaryocytes from 5 patients and 1 normal person were observed electronmicroscopically. In some pathologic states platelets seemed to be liberated without demarcation membrane system (DMS) and in a normal individual they seemed to be liberated independently of DMS. These findings suggest that DMS is not concerned with platelet liberation and that platelets are liberated through pseudopodia and bleb formation. In mature megakaryocytes vigorous amoeboid movement seems to exist and both pseudopodia and blebs may represent this movement. Structural similarity between surface connected system (SCS) of platelet and DMS of megakaryocyte suggests that the structure called DMS is transported as SCS into platelet.


[Material-testing studies for the rationalization of the technology of stomatological cold curing-plastics].

Materials scientific studies on the rationalization of the processing of stomatological cold-curing plastics. Hydropneumatic overpressure polymerization leads to a considerable rationalization of the processing of stomatological cold-curing plastics, but its effects on the course of polymerization and the properties of the polymerizate are yet not sufficiently elucidated. For this reason, the author studied in several test series the effects of various processing parameters (flask and overpressure vessel; varying mixing ratios, pressures and temperatures) on the polymerization of Kallocryl-AS, a cold-curing plastic. The results obtained indicate that, under certain processing conditions, overpressure polymerization of cold-curing plastics may be recommended from the viewpoint of materials science.


[Orthodontic therapy by tooth extraction--indication and prognosis].

From 1000 current orthodontic treatments, a percentage of 23.3 (233 patients) was selected for extraction therapy. The indication and the prognosis were analysed from various viewpoints to deduce suggestions for the application in practice. The advantages described and the possibilities of use meet the demands on efficient orthodontic therapy.


[An attempt at assessment of the numerical grading of success concerning diagnosis, therapy and prognosis in tooth alignment and malocclusion].

An attempt to assess the numerical grading of success with regard to the diagnosis, therapy and prognosis of anomalies of tooth alignment and occlusal position. Classifications according to Korkhaus, Angle and Eismann were evaluated using the original and final models of 42 patients who had been very co-operative. The importance and applicability in therapy and prognosis are assessed.


[Can changes be substantiated after termination of orthodontic treatment by means of yearly follow-up examinations? A longitudinal study over 5 years].

Is it possible to substantiate changes after terminated orthodontic treatment by annual follow-up examinations? A longitudinal study over five years. 42 patients with duly terminated orthodontic treatment were re-examined at intervals of one year during a period of five years. Relevant changes could be substantiated and discussed with regard to their importance in prognostic assessment.


[Stomatological studies of a Neolithic population from the collective grave at Schönstedt in Thuringia].

Of 64 burials at the Schönstedt common burial-ground which dates from the neolithic age, 49 well-preserved dentitions were examined for caries incidence, periodontal disease, abrasion, hypodontia and polydontia, tooth alignment and occlusal position. The results obtained are discussed with regard to contemporaneous and modern conditions.


[Stomatological studies of Merowingian skulls from the 5th and 6th century in Thuringia].

89 individuals of a Merovingian series from Weimar and Mühlhausen were examined for caries incidence, tooth abrasion, periodontal disease and dysgnathia. The results obtained were interpreted.


[Possibilities of an ergonomically designed working place].

Starting from a conventional stomatological work place, the author shows how to arrive stepwise, by reconstruction and new aquisitions, at two conceptions which enable the treating team to work in seated position.


[Construction and mode of action of a suction apparatus based on the vacuum cleaner principle].

Design and mode of action of a suction apparatus worked on the vacuum cleaner principle. A suction apparatus worked on the vacuum cleaner principle is presented as a part of a modern work-place conception.


[A new possibility of improving the breaking strength of mineral tooth facets by ion exchange ].

A 140% increase in the breaking strength of Keradens facings may be achieved by ion exchange, i.e., by substitution of the small sodium ions in soda feldspar by the larger potassium ions, which is done by melting the soda feldspar with potassium nitrate. The temperature and the time required for optimum exchange conditions are derived from the results of the present study.


[The effect of irrigation on the oxygen tension in the healthy rat gingiva].

The temperature of the rat's gingiva was 30.4 +/- 0.3 degrees C. before, and 37.1 +/- 0.2 degrees C. after irrigation. After irrigation, the oxygen tension in the gingiva of the rats was by 40% higher than its original value. When pure oxygen was inhaled, the tension increased by 120% before irrigation, and by 126% after irrigation.


[Diabetes and periodontal therapy].

The relationships of diabetes to periodontal diseases are still not elucidated. Due to the increasing morbidity of the two diseases, it becomes more and more frequent that they occurr both in the same patient. There is no doubt that periodontal disease is at least aggravated by diabetes. This is corroborated by the author's experienence. The control and dispensary treatment of diabetics by a stomatological nurse are regarded as a possibility of early detection of periodontal disease and, thus, of preservation of the teeth.


[Intraoral UV irradiation in gingivitis and ulcerative stomatitis].

The different specific and non-specific general effects of ultra-violet rays are discussed. Intro-oral ultra-violet irradiation is indicated  in all ulcerous and ulcero-aphthous diseases of the gingiva and the remaining oral mucosa. The author's experience does not plead for other applications, e. g., in case of parodontopathia inflammata and parodontopathia dystrophica, which is sometimes recommedned. The technique of ultra-violet irradiation is described. It is emphasized that a stomatological nurse may give this treatment, which relieves the stomatologist


[Fundamentals of applied oncology].

The fundamentals of applied oncology involve essential aspects: Intensive cancer prevention is necessary, which may be achieved by the elimination of certain environmental factors and the early recognition of premaligant and maligant growth processes, including an intensive fight against neglect and an extended health education. The WHO classification is an internationally understandable nomenclature. It is established and commented upon with regard to its specific application in practice. The importance of the dignity of tumour classes and types to prognosis and therapy is indicated. It is arranged in 7 qualities of dignity with corresponding types of neoplasms, with regard to transitional types between benign and malignant tumours. The definition of 4 tumoral stages according to the TNM system is intended for obtaining patient groups which permit to compare therapeutical results. The principle and application of the different therapeutical possibilites (surgical intervention, radiation therapy, chemotherapy, hormonotherapy, virus therapy, immunotherapy and complex treatment) are outlined. The rehabilitation and the after-care are of deciding individual, vocational and social importance to the resocialization of the tumour patients.


The effect of some local anaesthetics upon the electrical and mechanical activity of respiratory muscles in cats during pentobarbital anaesthesia.

No thorough investigation has been made of the effect of small intravenous doses of local anaesthetics upon respiration, although those agents are extensively used for clinical purposes. This prompted a study of the effects of rapid intravenous injections of 2 and 4 mg/kg lidocaine, 3 and 7 mg/kg mepivacaine and 0.4 and 0.8 mg/kg bupivacaine upon the electrical and mechanical activity of the respiratory muscles. Studies were also made of the effects of 3 mg/kg lidocaine when gas mixtures of different carbon dioxide and oxygen content were bein g breathed. The experimental animals were 43 cats, anaesthetized with 35 mg/kg pentobarbital intraperitoneally. Recordings were made of the number of impulses and the maximal impulse frquency from the external intercostal muscles, the diaphragm and the phrenic nerve, together with the tidal volume, minute ventilation, breathing frequency, duration of inspiration, and, during occluded breaths, the maximal pressure and the pressure impulses generated by the inspiratory muscles. It was found that all of the agents investigated had a clear effect upon respiration. The most marked changes became apparent during the first few minutes following the injections, and the effects lasted 10-20 minutes, as judged from changes observed in the recorded parameters. No differences could be seen in the effects of lidocaine and mepivacaine upon respiration, except as regards the effect upon inspiratory time. However, both of these agents differed from bupivacaine in the r effects. Lidocaine and mepivacaine depressed the activity of the external intercostal muscles, whereas the changes recorded from the diaphragm were much less marked...


Primary lymphomas of the central nervous system; in vitro culture observations.

Out of 960 human brain neoplasms seven primary lymphomas were cultured and grown up to twenty eight days. The monolayers had common cytological characteristics; /i/ immediately after plantation a high density of uniform cells was observed; /ii/ many cells were lost during subsequent medium changes; /iii/ the monolayers contained lymphocyte-like cells in different numbers. According to their individual characteristics the cultures could be classified into three categories: 1./ In the cultures of three tumours lymphocyte-like cells predominated. These tumours had low proliferative capacity in vitro. 2./ Cultures of three other tumours consisting mainly of tissue macrophages had a high proliferative capacity in vitro. 3./ Cultures of a single tumour showed the combined features of the former two categories: both lymphocyte-like cells, and tissue macrophages were present. These cultures showed the highest proliferative activity. On the basis of these findings it is quite possible that beside other methods, tissue culture technique may be useful in the classification of brain lymphomas.


[Spontaneous nitroblue terazolium reduction test (NBT) by peripheral blood granulocytes in healthy subjects and in some hematologic syndromes].

The NBT reduction test and determination of alkaline phosphatase activity in the peripheral blood granulocytes (FAG) were done in 94 subjects including 30 blood donors donating blood for the first time and 64 cases of various haematological syndromes. Raised proportion of formazan granulocytes was found in patients with pancytopenia, acute myeloid leukaemia, chronic myeloid leukaemia during blastic exacerbation, Hodgkin's disease during exacerbation and lymphosarcoma. These results correlated with increased FAG activity. Lower proportions of formazan granulocytes capable of spontaneous reduction of NBT were found in patients with chronic myeloid leukaemia, in immunohaemolytic anaemias and in plasmocytoma. Of all the above syndromes only in chronic myeloid leukaemia impaired ability of formazan cell formation parallelled decreased FAG activity. In the remaining syndromes FAG activity in the granulocytes was normal or raised. In the remissions of Hodgkin's disease a fall was observed in the proportion of formazan granulocytes to values of FAG. In chronic myeloid leukaemia the proportion of formazan cells showed considerable fluctuations and no correlation was observed between the proportion of formazan cells and FAG activity.


A comparison of the fine structure of malignant lymphoma and other neoplasms in the brain.

The fine structure of a primary intracranial lymphoma was examined and compared with that of a group of central nervous system tumors comprised of medulloblastoma, oligodendroglioma, ependymoma, ependymoblastoma. The principal difference was the absence of any junctional devices on the principal tumor cells of the lymphoma and their presence in the other tumors. It is suggested that this difference reflects the difference in origin of these tumors.


[Results of immunotherapy of acute leukemias with BCG vaccine of Polish production].

In 18 patients with acute leukaemia complete remission was obtained by chemotherapy and it was tried then to prolong remissions repeating at weekly intervals BCG immunization by the method of searification. In one patient no response was obtained, in 5 cases leukaemic exacerbations occurred after withdrawal of cytostatic agent. Twelve patients were maintained in complete remission during BCG vaccinations for 3.5 to 37 months. Presently only 2 patients remain in remission from 14 to 37 months with repeated BCG vaccinations only. In the remaining cases exacerbations developed after 3 to 17 months of vaccinations. The same cytostatic agents were administered to which the patients had responded previously favourably before starting vaccinations and new remissions were obtained again lasting from 3 to 24 months. Six patients died 4 to 19 months after withdrawal of BCG vaccinations. Autopsy confirmed the diagnosis of acute leukaemia.


Ultrastructural study of two central nervous system lymphomas.

Electron microscopy was performed on two CNS lymphomas, one primary and the second a skull metastasis from a brain primary lymphoma. The former revealed a tumor perivascularly arranged, which was composed of rounded cells having no specialized organellae. Biopsies from the primary and metastasis of the second case revealed a predominance of rounded cells with scanty cytoplasm, another population of cells with phagocytic activity and a third group with elongated ctyoplasmic processes which stain positively for microglia. By electron microscopy some of these processes resembled neurites or oligondendroglia, while others suggested an astrocytic appearance.


The ulstratructure of reticulin.

The electron microscopic examination of various organs and tumours of different species proved that the ultrastructural equivalent of reticulin fibres is not a uniform substance. Reticulin fibres are either basement membranes or an amorphous mass which appears as argyrophil fibres under the light microscope. Microfibrils may in some cases produce an argyrophilic reticulum. The claimed identity of reticulin and collagen can partly be explained by the chemical similarity of collagen and basement membranes. It seems possible, moreover, that the amorphous mass and microfibrils, which may be an ultrastructural substrate of reticulin, are composed of a material essentially similar to that of collagen.


Cytology of the cerebrospinal fluid in patients with Hodgkin's disease or malignant lymphoma.

The cerebrospinal fluids (CSF) of 18 patients with Hodgkin's disease and 33 patients with malignant lymphoma were evaluated for the presence of malignant cells. The CSF  cytology was correlated with the neuropathologic findings at surgery or autopsy. In the 51 patients included in the study there were seven false-negative CSF cytodiagnoses. Methods to improve detection in the false-negatives will be discussed. There were two false-positives. Explanations for the two false-positive cytodiagnoses will be presented. It is concluded that cytological examination of the CSF in patients with Hodgkin's disease and malignant lymphoma is a useful and reliable diagnostic tool.


Electron microscopy of lymphocytic leukaemia cells in the cerebrospinal fluid.

The ultrastructure of cells in the CSF are reported in 2 cases of lymphocytic leukaemia of the CNS. Unusual nuclear pockets, margination of the nuclear chromatin and fragmentation of the nuclei were frequent in the first case, whereas in the second nuclear pockets were rare and deep indentations of the nuclei frequent.


Family studies in cases with malignant lymphomas.

A short review of the genetic aspects of tumors of the reticuloendothelial system is given. Of special interest is the observation of a "familial lymphohistiocytosis of the nervous system" published by PRICE et al. in 1971. Important are also our own observations with different types of malignant lymphoma in the same family. In addition to the possibilities of classical mendelian inheritance and the possibility of multifactorial inheritance preexisting immunological deficiency syndromes and chromosomal aberrations have to be considered as causal factors.


Lymphoblastic extramedullary spinal tumor during remission of acute lymphoblastic leukaemie.

An unusual case history of a girl with ALL is presented. The diagnosis was established at the age of 7. At the age of 11, 5 years and 3 months after remission due to treatment an extramedullary tumour of a lumbar vertebra produced a transverse lesion of the spinal cord and meningeal leukaemia. The tumour consisted mainly of connective tissue with small foci of lymphoblastic cells, identical with those originally seen in the peripheral blood stream. After laminectomy, irradiation and chemotherapy the girl is still in her first haematological remission, lasting nearly 7 years.