Isobaric force-velocity relationship of in situ canine trachealis muscle

We measured the force-velocity relationship of the in situ trachealis muscle during vagal stimulation in six anesthetized dogs. The trachea, about 10 cm in length, was transected above the carina and left in situ with its blood supply intact, and its cut ends artificially closed. The lung was ventilated by a respiratory. First the vagal nerves were electrically stimulated to induce isometric contractions which resulted in an increase in tracheal pressure; then the tracheal volume was reduced to a rate (velocity) which kept the tracheal pressure constant at a given level (force). The force-velocity curve was hyperbolic. Using Hill's equation, we calculated the values of P0 (the maximum force at 10, lo being the trachealis muscle length at which the maximum active tension develops) and Vmax (the maximum velocity at zero afterload). They were P0 = 0.85 +/- 0.20 kg/cm2 and Vmax = 0.08 +/- 0.02 l0/s. We concluded that both force and velocity of the trachealis muscle in situ exhibited lower values than those in vitro.

Effects of norepinephrine infusion on systemic hemodynamics and plasma 6-keto-prostaglandin F1 alpha in normotensive subjects and patients with essential hypertension

Altered prostacyclin metabolism may underlie essential hypertension. In this study, responses of plasma 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha: a stable metabolite of prostacyclin) to infused norepinephrine (NE) were compared in 14 normotensive subjects (NT) and 20 untreated patients with essential hypertension (EH). In addition, changes in systemic hemodynamics following NE-infusion were compared with changes in plasma 6-keto-PGF1 alpha. The subjects were all hospitalized and placed on a diet containing 6-8 g of salt per day. Blood pressure was recorded directly through the brachial artery, cardiac output (CO) was determined with the dye-dilution technique using cuvette and total peripheral vascular resistance (TPR) was calculated before and 60 min after NE-infusion. Arterial plasma 6-keto-PGF1 alpha was also determined before and after NE-infusion. The rate of NE-infusion was adjusted to elevate mean arterial pressure (MAP) by 10-15%. Plasma 6-keto-PGF1 alpha was radioimmunoassayed. Elevation of MAP was 13.0 +/- 1.2 (SE) in NTs and 11.7 +/- 1.4% in EHs. After NE-infusion, CO and TPR both significantly increased in NTs, while only CO increased significantly in EHs. Changes in CO and TPR were both significantly different between the two groups (p less than 0.01). Initial plasma 6-keto-PGF1 alpha was reduced in EHs as compared with NTs (174 +/- 15 vs 295 +/- 41 pg/ml, p less than 0.02). However, during NE-infusion, the increase in plasma 6-keto-PGF1 alpha was greater in EHs than in NTs (p less than 0.01). There was a significant negative correlation between changes in TPR and plasma PG (r = -0.36, p less than 0.05). The results indicate that responses of systemic hemodynamics and plasma 6-keto-PGF1 alpha to infused NE are different in the NT and EH groups, and that the absence of changes in TPR in EHs may be related to a marked increase in circulating prostacyclin. These findings, together with the reduced initial levels of plasma 6-keto-PGF1 alpha in EHs, probably represent altered prostacyclin metabolism in essential hypertension.

[Assay of anti-cancer drug sensitivity of cells from human tumors. Detection of cell viability with radioisotope (author's transl)]

An attempt has been made to construct an assay of anti-cancer drug sensitivity which is suitable for use with primary culture cells from human bone and soft tissue tumors. The ability of cells to incorporate labeled nucleic acid precursors into acid precipitable material was assessed. Hela-S3 cells were employed to avoid inherited variability and heterogenity of primary cultures of human tumors. Labeled nucleic acid precursors were used not to assay the changes of DNA or RNA synthesis but to detect the viability of cells. A logarithm of counts per minute of incorporated labeled precursors is in proportion to a logarithm of viable cell numbers. This relationship was not influenced by the labeled precursor incubation time. Multiplate was used to provide large numbers of replicate cultures without the requirement of a large numbers of cells. Monolayer Hela-S3 cells which were seeded 24 hours earlier were incubated for three hours with various concentrations of drugs. After removal of drugs, cells were cultured for one week. In this period, Hela-S3 cells with no drug treatment became almost confluent and mitoses occurred about four times. Labeled precursors were incubated for three hours, and incorporated 3H-thymidine was counted. A standard curve of incorporated labeled precursor counts and viable cell numbers was drawn for every assay. The density inhibition of labeled nucleic acid precursor incorporation can be checked and connected with the standard curve, and viable cell numbers after drug exposure can be obtained from the standard curve. When percent survival is plotted against drug concentration, a sigmoid curve is obtained if the drug has dose dependent effect and then the 90% lethal dose (LD90) can be determined from the curve. LD90 was used as the index of anti-cancer drug sensitivity. If the drug has time dependent effect, percent survival of maximal inhibition was used as the index of drug sensitivity.

Histochemical localization of kallikrein-like Pro-Phe-Arg-naphthylester esterase activity in the rat kidney

In the rat kidney the presence of the kallikrein-like pro-phe-argnaphthylester esterase activity was demonstrated by a simultaneous coupling azo dye method. The enzyme was identified as a serine-protease because it was inhibited by preincubation with diisopropyl-fluorophosphate and unaffected by sodium iodoacetate. Since kallikrein is a serine-protease and prophe-arg-naphthylester is a synthetic and sensitive substrate for kallikrein, the enzyme activity revealed by this method was considered to represent kallikrein, although non-kallikrein esterase activity is not totally excluded. The enzyme activity was localized mainly in the outer stripe of the outer medulla, with focal extensions primarily only in the lower half of the cortex corresponding to the medullary rays.

Computed tomography in the diagnosis of fatty liver: total lipid content and computed tomography number

Fifty-three histologically proved cases of various diffuse liver disease were studied for their computed tomography numbers (CTN). The machine used was Ohio Nuclear's Delta Scanner 50FS type and CTN was expressed by the Hounsfield unit (H). Mean CTN in each group was as follows: 66.6 +/- 2.6 H in normal control (N), 63.3 +/- 6.0 H in chronic hepatitis (CH). 61.8 +/- 7.0 H in liver cirrhosis (LC), and 44.4 +/- 10.6 H in fatty infiltration (FI). There were no significant differences among them except FI group. As N group were all above 60 H and CH and LC groups were all above 50 H, CTN below 60 H suggests chronic liver disease or fatty infiltration and CTN below 50 H strongly suggests fatty infiltration. In eleven cases where total lipid content of the liver could be be biochemically determined by the sulfo-phospho-vanillin reagent, a relation of total lipid content to CTN was studied. As a result, a significant correlation existed between them (r = -0.89; p less than 0.001). If the diagnostic criterion of fatty liver was set at total lipid content above 100 mg/g wet liver, CT criterion was estimated at CTN below 48 H from the regression formula.

Inhibition of 12-O-tetradecanoylphorbol-13-acetate-induced epidermal ornithine decarboxylase activity by lipoxygenase inhibitors: possible role of product(s) of lipoxygenase pathway

Induction of epidermal ornithine decarboxylase (ODC) by a topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA), a tumor promoter, was inhibited by treatment of mouse skin with phenidone (3-90 mumol/mouse), nordihydroguaiaretic acid (30 mumol/mouse) or 3-amino-1-[m-(trifluoromethyl)-phenyl]-2-pyrazoline (BW 755C, 30 mumol/mouse), which are well-known lipoxygenase inhibitors. Phenidone and BW 755C are also to be cyclooxygenase inhibitors. Inhibition of TPA-induced ODC by indomethacin (1.12 mumol/mouse), a selective cyclooxygenase inhibitor, was counteracted by prostaglandin E2 (PGE2) (140 nmol/mouse). This counteracting effect of PGE2 was reversed by the treatment of mice with nordihydroguaiaretic acid (30 mumol/mouse) or phenidone (30 mumol/mouse). ODC activity which was suppressed by nordihydroguaiaretic acid or phenidone at a dose of 180 mumol/mouse was not further inhibited by indomethacin (1.12 mumol/mouse). In addition, the counteracting action of PGE2 (140 nmol/mouse) was not observed in mice treated with nordihydroguaiaretic acid or phenidone at a dose of 180 mumol/mouse. Thus, the suppressive effect of nordihydroguaiaretic acid or phenidone on the ODC induction by TPA would be due to the inhibition of lipoxygenase. The above findings strongly suggest that not only cyclooxygenase product (i.e., PGE2) but also lipoxygenase product(s) are involved in the mechanism of ODC induction in mouse epidermis, and a lack of either cyclooxygenase product or lipoxygenase product(s) causes a failure of ODC induction by TPA.

Macular amyloidosis with patchy filamentous degeneration of collagen islands

Unusual patchy filamentous degeneration of collagen islands, found in a typical case of macular amyloidosis, is described. This phenomenon was found to begin in intact islands scattered among the amyloid islands in the papillary and upper reticula dermis. Since the patches varied in size, they were thought to have grown gradually with time. They were derived from the degeneration of collagen fibrils and demonstrated a tropocollagen-like structure. Although the small patches preserved some characteristic structures of collagen fibrils or tropocollagen, the large patches showed amyloid-like filamentous masses surrounding the collagen islands.

Early cancer of the stomach treated successfully with an endoscopic neodymium-YAG laser: report of a case

A 61-year old man with poor pulmonary function was seen with two early cancers of the stomach. Neodymium-YAG laser treatment was applied to these lesions since surgery was contraindicated. The lesions were treated four times. Both tumors completely disappeared and the patient was left with ulcer scars that formed three to seven months after the treatment. Our results suggest that endoscopic Nd-YAG laser therapy is applicable in the treatment of early gastric cancer when a surgical operation is contraindicated.

A new murine model of accelerated senescence

Five senescence-prone series of mice (P-1, P-2, P-3, P-4 and P-5) and three senescence-resistant series (R-1, R-2 and R-3) were obtained by continuous sister-brother breeding from five original litters of AKR mice with severe deterioration, and the three original litters of AKR mice with normal aging, respectively. A grading score system was adopted to evaluate the degree of senescence of these mice and a steady and irreversible increase in this grading score was seen with advancing age in both the R and P series. The high grading score in the P series was due to an earlier onset of loss of passivity and reactivity, loss of skin glossiness and increased coarseness, hair loss, periophthalmic lesions, increased lordokyphosis of the spine and a more marked increase in their severity with advancing age as compared to the R series. Among the P series, P-2 showed a 100% incidence of systemic amyloidosis after 6 months of age and P-3 a 70% incidence of cataract over 16 months of age. The life span in the P series was shortened by about 26% of that of the R series. In view of the evidence obtained from the survivors, the growth rate and Gompertz function, the aging pattern in the P series was considered to be an acceleration of senescence. The P series has been named "SAM" ("Senescence Accelerated Mouse").

[The effects of the angiotensin converting enzyme inhibitor, captopril, on catecholamine concentrations in rat plasma, heart, brain and kidneys (author's transl)]

Two studies were designed to examine the effect of the angiotensin converting enzyme inhibitor, captopril, on the sympathetic nervous system. In the first study, blood pressure (BP), heart rate (HR), and norepinephrine (NE) concentrations in the heart were measured in rats which had been given the agent orally in tap water (0.5 mg/ml) for 2, 9, 19, 29, and 58 days. BP and HR were measured using a tail-microphone to which a tachometer to record HR was connected in the unanesthetized and unrestricted condition. Heart NE was extracted with perchrolic acid and measured with the THI method on a high pressure liquid chromatography. The same study was also done in the control rats. The BP of the rats which had been given captopril for 9 days or more was significantly lower than in the control rats, while HR was not different between the two groups of rats. The ratio of heart weight/body weight was significantly lower in the captopril rats than in the control rats 58 days after the captopril administration. The ratio was significantly correlated with BP in these captopril and control rats (r = 0.59, p less than 0.01). In contrast to the control rats, the NE concentrations in the heart gradually increased in the captopril rats, thus being significantly higher in the latter than in the former after 29 and 58 days of captopril administration (p less than 0.01 for both observations). In addition, the lower the BP was, the higher the NE concentrations in the heart was in all the rats (r = 0.52, p less than 0.001). In the second study, BP, HR, and NE concentrations in plasma, heart, brain and the left kidney were measured in rats which had been on captopril for 2 and 29 days. Renal renin content (RRC) was also measured in the right kidney. In this study, BP and HR were recorded through a carotid catheter which had been inserted 4 hrs previously under light ether anesthesia. BP was significantly lower and NE concentrations in the heart was higher in the captopril rats than in the control rats after 29 days of captopril administration. There was a significant negative correlation between BP and NE concentrations in the heart in the captopril and the control rats (r = -0.88, p less than 0.001). No difference in HR was found between the 2 groups. NE concentrations in plasma, brain and kidney showed no significant differences between the captopril and the control rats in either of the stages of sacrifice. RRC was markedly reduced in the rats with 2 days of captopril, while it increased in the rats with 29 days of captopril. However, the RRC had no definite relationship with the NE concentrations in plasma or that in the kidney. The results show that chronic administration of captopril reduces the heart weight in normotensive rats. This effect points on the one hand to a decrease in "cardiac after-load" and on the other to changes of humoral factors such as plasma angiotensin II induced by captopril...

Cutaneous ultrastructural diagnosis of ceroid-lipofuscinosis

A skin biopsy from a 6-year-old girl was examined by electron microscopy and the diagnosis of ceroid-lipofuscinosis (CL) was confirmed. This has not been reported in the dermatology literature, because of the absence of specific skin manifestations. However, as we have shown, various cells of skin, including fibroblasts, Schwann cells, eccrine serous cells, endothelial cells and smooth muscle cells, accumulated characteristic substances to produce the finger print pattern (FPP) or the curvilinear profile (CLP) which are thought to be diagnostic for CL. Cutaneous ultrastructural research in such cases is important as asymptomatic skin disorders may exist in other congenital storage diseases.

Series distribution of airway collapsibility in dogs

We studied the series distribution of collapsibility in four different-sized airways in dogs. The trachea and the extrapulmonary main bronchi in situ were isolated from the rest of the lungs by glued beads of 6-12 mm OD. In excised dog lungs, the intrapulmonary large and small bronchi were isolated from the rest of the lung by glued beads of 1-9 mm OD. Pressure-volume relationships were measured directly in the trachea and in the extrapulmonary bronchi; those of the intrapulmonary bronchi were derived from orthogonal bronchograms. Airway collapsibility, defined as the slope of the pressure-volume curve, was found to increase in all airways as transpulmonary pressure (PL) decreased. At PL 30 cmH2O there was little difference of airway collapsibility among the different sized airways; but, as PL decreased, the peripheral airways became more collapsible than the central airways. It is concluded that the tissues surrounding the trachea provided as much or more stiffness than did the lung tissues that surrounded the intrapulmonary airways. The larger collapsibility in the peripheral airways. The larger collapsibility in the peripheral airways relative to that of the central airways at lower PL may account for the peripheral migration of the flow-limiting segment during forced expiration.

Estrogen induces different responses in dermal and lung fibroblasts: special reference to collagen

Fibroblast-like cells derived from dorsal skin and lung of AKR strain mouse embryos were cultured with estrogen for 4 days. The labeled hydroxyproline content was measured as newly synthesized collagenous protein in the cell layer and media. Although collagen synthesis by both cell lines was increased in both fractions under the influence of beta-estradiol-3-benzoate, at physiological concentrations of 10(-3)-10(-1) microgram/ml, the rate of increase differed. Fibroblasts derived from skin showed increased collagen synthesis of approximately 76%, while those from lung showed an increase of approximately 25%. Total protein synthesis by both cell lines also increased. In lung fibroblast cultures the synthesis of total protein was increased more than the synthesis of collagens; on the other hand in skin fibroblast cultures the synthesis of collagen was increased more than the synthesis of total protein. DNA synthesis by both cell lines was not affected by estrogen at the concentrations used. These findings suggest that fibroblasts develop in a different manner in each organ.