In the present investigation a comparison was made between conventional histology, histochemistry and vital microscopy for assessment of heat-induced bone tissue injury. The extent of the bone damage around a burr hole or after heating fibular bone samples in saline solutions of various temperatures was evaluated by means of histology and histochemistry, using the absence of filled osteocyte lacunae or lack of oxidative enzyme activities as indication of bone death, respectively. In both cases a wider necrotic border zone was detected with histochemistry than with histology. The vital microscopic method is based on a titanium chamber which, after insertion in the rabbit tibia, allows observation and registration of the same bone compartment for a follow-up period of more than one year. The dynamic tissue events taking place after heating to 50 degrees C for one minute were investigated and compared with histological and histochemical data of the bone. The vital microscopic method showed a consistent and widespread bone tissue injury after heating to 50 degrees C for one minute while, on the other hand, the indirect methods exhibited only inconsistent signs of tissue injury. It is concluded that histochemistry using the presence or otherwise of diaphorase enzyme activities is a more reliable method than is histology for the estimation of bone viability after heat trauma. Vital microscopy is more sensitive than indirect, morphologic and metabolic techniques for detection of heat-induced bone tissue injury.

In Sweden, snu (locally known as snus), was introduced since the year 1637. Presently, Sweden has the highest per capita consumption and sale ®gures of snu in the world, and the habit is becoming increasingly popular. Snus is manufactured into a dry form used in the nasal cavity and a moist form used in the oral cavity. Snus manufactured for oral use is a moist ground tobacco of Dark Kentucky or Virginia species mixed with an aqueous solution of water and other blending ingredients. This form of snu is found in two types: (1) loose and (2) portion-bag-packed. These are the most widely used. The loose moist form (1±2 g a quid) is the most popular type consumed by 73% of the males, followed by the portion-bag-packed form (0.5±1 g a quid), consumed by 13% of the males, while 14% of the males are mixed users. The majority of snus users place the quid in the vestibular area of the upper lip, and the prevalence among persons 15 years of age or older is 15.9% among males and 0.2% among females. The pH of snus has declined from a previous range of 8±9 to a range of 7.8±8.5, moisture content ranges 35±60% and nicotine content is in the order of 5±11 mg/g dry wt tobacco-speci®c N-nitrosamines (TSNAs) in micrograms (N H -nitrosonornicotine: NNN 5±9; 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone: NNK 1±2; N H -nitrosoanatabine: NAT 2±5). In the Sudan, snu, locally known as toombak, was introduced approximately 400 years ago. It is always processed into a loose moist form, and its use is widespread in the country. Tobacco used for manufacture of toombak is of the species Nicotiana rustica, and the fermented ground powder is mixed with an aqueous solution of sodium bicarbonate. The resultant product is moist, with a strong aroma, highly addictive and its use is widespread particularly among males. Its pH range is 8±11, moisture content ranges 6±60% and nicotine content is from 8 to 102 mg/g dry wt, and TSNAs contents in micrograms (NNN 420±1 550; NNK 620±7 870; NAT 20±290). Snus and toombak dippers develop a clinically and histologically characteristic lesion at the site of dipping. Probably due to control of the TSNAs in snus, this type of snu is associated with a lower risk of cancer of the oral cavity (relative risk: RR 5±6-fold), whereas the risk for cancer of the oral cavity among toombak users was high (RR 7.3±73.0-fold). In conclusion, the two snu products signi®cantly dier in many aspects. Most notable dierences are tobacco species, fermentation and ageing, nicotine and TSNAs content, pH, expression of the p53 tumour supressor gene, and keratin types 13, 14, and 19. It was, therefore, the object of the present study to highlight the oral health hazards of toombak, and to compare it with snus regarding the aforementioned dierences. #

Serum T4, T3, rT3, free T4, free T3 and TSH were measured during and after normal pregnancy in 20 women. Special methodological precautions were taken to avoid interference of other hormones and protein alterations in the assays. Serum T4 and T3 were steadily increasing during the last part of the 1st trimester, and remained high and nearly stable during the 2nd and 3rd trimester of the gestation period. The high levels were approximately 1.5 times the values measured 10 weeks post-partum. Serum rT3 was elevated already during the last part of the 1st trimester and remained high throughout pregnancy, compared to the post-partum value. Serum free T4 and free T3 were slightly elevated in early pregnancy. The values decreased gradually during pregnancy and were slightly depressed during the 3rd trimester. A gradual increase in serum TSH was observed during pregnancy and the 2nd and 3rd trimester values were significantly higher than the post-partum value.The mean values for serum TSH, free T4 and free T3 remained always well within the normal range. Thus small variations in serum free iodothyronines and TSH occur during normal pregnancy, the alterations observed in the last trimester of the gestation period resembling those of a slight thyroid insufficiency. These trends in variation of the reference values are worth to remember in the diagnosis of borderline hypo-or hyperthyroidism and in the balanced treatment of pregnant women with thyroid dysfunction.High levels of thyroid hormones in serum due to increased cirulating TBG is a well known feature during normal pregnancy. Various measures of free thyroid hormones have been introduced in order to aid the diagnosis and control of thyroid dysfunction during pregnancy. Earlier investiga¬ tors have claimed that the amounts of free circulat¬ ing hormones are little affected by pregnancy (Burrow et al. 1975;Pekonen & Lamberg 1978;Ekins 1979). Further, serum TSH has been found nearly unaltered too (Burrow et al. 1975;Pekonen & Lamberg 1978).However, due to high serum levels of hCG, FSH and LH possibly interfering in the TSH assay and methodological difficulties in measuring free T4 and free T3 it is still not firmly established whether minor variations in free hormones and TSH occur during normal pregnancy. It is generally accepted that it is important to keep thyroid function near to normality during pregnancy in patients treated for thyroid disease; it is therefore important to know the normal variations. In the present study we have obtained repeated blood samples from normal women during and after pregnancy and taken special methodological precautions to avoid inter¬ ference of other hormones and protein alterations in the assays. Materials and MethodsTwenty healthy pregnant women were asked to partici¬ pate in the investigation at their first visit to their general practitioner for pregnancy control. They constituted a consequtive series of healthy pregnant women contacting a suburb clinic with 4 general practitioners. Excluded were pregnant women who paid their firs...

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From October 1983 until December 1988, 50 patients with asymptomatic multiple myeloma stage I were included in a prospective randomized multi‐centre study comparing melphalan‐prednisone (MP) therapy started at the time of diagnosis with deferred therapy where MP was started at the time of disease progression. Twenty‐five patients were randomized to each group. The median time from diagnosis to start of therapy in the group with deferred therapy was 12 months. The reasons for starting therapy were increasing M‐protein in 8 cases, symptomatic bone disease in 9 and anaemia in 5. In 2 cases, disease progression was complicated by vertebral fractures necessitating radiotherapy. Two patients in the group in which MP was started at the time of diagnosis developed acute leukaemia. No differences in response rate, response duration or survival were observed between the treatment groups. We conclude that in asymptomatic myeloma deferral of chemotherapy is feasible in well‐informed and well‐controlled patients but conveys no advantage in survival. In clinical practice the benefits of treatment deferral are to some extent outweighed by disease progression before start of treatment.