Persistence of the stapedial artery: a histopathologic study

Persistence of the stapedial artery is a rare event. Fewer than 30 cases have been reported since the discovery of this artery in 1836. We carried out a histopathologic study on three temporal bones from two patients who had this anomaly, and were able to trace the full course of the artery. In two specimens a large stapedial artery persisted and substituted for the middle meningeal artery. In the third, a small, persistent stapedial artery ended in the arterial plexus surrounding the facial nerve. Persistence is discussed in terms of embryogenesis, developmental theories, histologic findings, and clinical significance. The material suggests that the stapedial artery can persist to varying degrees.

Antitumor effects of gossypol on murine tumors

Since the male antifertility drug, gossypol, was shown to be a specific inhibitor of DNA synthesis at moderately low doses in cultured cells, its antitumor potential has been evaluated in three murine tumor models. The effects of gossypol on tumor growth and the survival of 10- to 12-week-old BDF1 mice bearing mouse mammary adenocarcinoma 755 (Ca 755) or P388 or L1210 leukemias, all injected IP, were measured. At an optimum dose of 0.5 mg/mouse given as a single injection at 2 days (48 h) after the inoculation of 10(5) Ca 755 tumor cells, gossypol rendered 66% of the mice free of tumor cells, whereas the remaining 34% died of drug toxicity. The survival rate decreased sharply at doses on either side of the optimum. At suboptimal doses a major proportion of the tumor-bearing mice died of tumor, whereas at higher doses all the animals died of drug toxicity. In other words, the effective dose range of gossypol was rather narrow. The rapidly proliferating mouse leukemias, P388 and L1210, failed to respond to gossypol. Histopathological studies of various organs in the gossypol-treated mice revealed no consistent lesions that could give an indication of organ-specific toxicity of gossypol. The reduction in the myeloid series in the bone marrow of gossypol-treated mice may have been due to depletion rather than direct toxic effect. Further studies are essential to evaluate this compound with regard to its antitumor activity in other murine models.

Temporal bone fractures: a histopathologic study

Trauma or injury to the skull, if of sufficient force, may produce a temporal bone fracture. However, terms such as basilar skull fracture, labyrinthine hemorrhage, or labyrinthine concussion are inadequate in that they do not describe the precise histopathologic lesion. We carried out a histopathologic study of the 14 ears in seven patients; all the patients suffered at least one temporal bone fracture. Our objective was to review the histopathologic findings of various fracture lines through the base of the skull and correlate these with the history and clinical findings.

Dual action of respiratory inhibitors: inhibition of germination and prevention of dormancy induction in lettuce seeds

;Grand Rapids' lettuce Lactuca sativa L. seeds germinate readily at 15 degrees C but poorly at 25 degrees C in darkness. When held in dark at 25 degrees C for an extended period, the ungerminated seeds become dormant as shown by their inability to germinate or transfer to 15 degrees C in darkness. Induction of dormancy at 25 degrees C was prevented by exposure to CN(-), azide, salicylhydroxamic acid (SHAM), dinitrophenol, and pure N(2) as determined by subsequent germination at 15 degrees C on removal of inhibitors. The effectiveness of inhibitors to break dormancy declined as dormancy intensified. At relatively low levels, CN(-), SHAM, and azide promoted dark germination at 25 degrees C while at high levels they were inhibitory. Uptake of O(2) by seeds held at 25 degrees C for 4 days in 1.0 millimolar KCN was inhibited by 67% but was promoted 61% when KCN was removed. Correspondingly greater inhibition (79%) and promotion (148%) occurred when 1.0 millimolar SHAM was added to KCN solution. When applied alone, SHAM had little effect on O(2) uptake. These data indicate that Cyt pathway of respiration plays a dominant role in the control of both dormancy induction and germination of lettuce seeds, and ;alternative pathway' is effectively engaged in presence of CN(-). The channeling of respiratory energy use for processes governing germination or dormancy is subject to control by physical and chemical factors.A scheme is proposed that illustrates compensatory use of energy for processes controlling dormancy induction and germination. A block of germination, e.g. by low water potential polyethylene glycol solution or a supraoptimal temperature spares energy to be utilized for dormancy induction while a block of dormancy induction by low levels of CN(-) (similar to GA and light effects) drives germination. Blocking both processes by inhibitors (e.g. CN(-), CN(-) + SHAM) presumably leads to accumulation of ;reducing power' with consequent improvement in O(2) uptake and oxidation rates of processes controlling germination or dormancy induction upon removal of the inhibitors.

Immunological detection of cloned antigenic genes of Vibrio cholerae in Escherichia coli

Antibodies have been used as probe to detect cloned genes coding for toxin and surface antigens of Vibrio cholerae El Tor strain KB207. EcoRI-digested chromosomal DNA of KB207 was cloned in plasmid pBR325 and transformed in Escherichia coli HB101(lambda cI857). Transformants were grown at 32 degrees C on plates containing antibodies. Lysogen was induced at 42 degrees C to release expressed antigens. Antigen-antibody reaction produced a halo around positive clones.

Depression of murine natural killer cell cytotoxicity by isobutyl nitrite

We have investigated the effect of isobutyl nitrite on murine NK-cell antitumor-directed cytotoxicity. This agent has been suggested as one of the factors underlying immunodeficiency syndrome (AIDS) in man. We demonstrated that two injections, each of 0.25 ml isobutyl nitrite, resulted in significant depression of endogenous splenic and peripheral blood natural killer (NK) cell cytotoxicity against T-cell lymphoma, YAC-1. In addition to endogenous NK cells, activity of pyrimidinol-activated NK cells was also substantially depressed by this agent. The latter observation is of the utmost importance, since it suggests that the attempt to augment NK-cell activity (to promote resistance to infections and malignancies) could fail in patients with AIDS who are isobutyl nitrite users. Isobutyl nitrite was NK-cell-suppressive not only after in vivo administration but, most importantly, also after inhalation. This indicates that isobutyl nitrite, via its NK-cell suppressive effect, could contribute to immunodeficiency in AIDS. Studies on the mechanism of NK-cell depression by isobutyl nitrite demonstrated that the NK-cell tumor-binding properties as well as NK-cell cytotoxic potential were substantially depressed. Mixing experiments failed to reveal any regulation by suppressor cell activities. The results of these studies clearly indicate that isobutyl nitrite is an immunosuppressive agent and that its use should be avoided.

Dispersed sensory ganglion cells cleave an active entity from nerve growth factor coupled to Sepharose

Dispersed sensory ganglion cells from the embryonic chick, but not cells from other tissues, liberate biologically active material from nerve growth factor coupled to Sepharose beads. Experiments with such insolubilized material cannot then be taken as evidence for the existence of an external membrane receptor for the factor and may indicate that responsive cells have the ability to cleave an active fragment from the polypeptide.

Delayed pseudopregnancy in the mouse

Treatment of female mice with bromocriptine on Day 1 or 3 of pregnancy induced many of the females to return to oestrus. The incidence of extended cycles (7--10 days) and pseudopregnancies following this return to oestrus was significantly higher than in unmated control females. These observations are consistent with the existence of a 'mnemonic' component of the luteotrophic system in the mouse.

Induction of Secondary Dormancy in Chenopodium bonus-henricus L. Seeds by Osmotic and High Temperature Treatments and Its Prevention by Light and Growth Regulators

Factors controlling the establishment and removal of secondary dormancy in Chenopodium bonus-henricus L. seeds were investigated. Unchilled seeds required light for germination. A moist-chilling treatment at 4 C for 28 to 30 days removed this primary dormancy. Chilled seeds now germinated in the dark. When chilled seeds were held in the dark in -8.6 bars polyethylene glycol 6000 solution at 15 C or in water at 29 C a secondary dormancy was induced which increased progressively with time as determined by subsequent germination. These seeds now failed to germinate under the condition (darkness) which previously allowed their germination. Continuous light or daily brief red light irradiations during prolonged imbibition in polyethylene glycol solution at 15 C or in water at 29 C prevented the establishment of the secondary dormancy and caused an advancement of subsequent germination. Far red irradiations immediately following red irradiation reestablished the secondary dormancy indicating phytochrome participation in "pregerminative" processes. The growth regulator combination, kinetin + ethephon + gibberellin A(4)+A(7) (GA(4+7)), and to a relatively lesser extent GA(4+7), was effective in preventing the establishment of the secondary dormancy and in advancing the germination or emergence time. Following the establishment of the secondary dormancy by osmotic or high temperature treatments the regulator combination was relatively more active than light or GA(4+7) in removing the dormancy. Prolonged dark treatment at 29 C seemed to induce changes that were partially independent of light or GA(4+7) control. The data presented here indicate that changes during germination preventing dark treatment determine whether the seed will germinate, show an advancement effect, or will become secondarily dormant. These changes appear to be modulated by light and hormones.

Preliminary in vitro study of diazepam and droperidol on oestrus rat uterus

The actions of diazepam and droperidol were studied on the spontaneously active and oxytocin-treated oestrus rat uterus. Both drugs significantly depressed the frequency of uterine contraction. Droperidol reduced the amplitude of contractions and the basal tone of the tissue. The sensitivity of the tissue to both drugs was enhanced in the presence of the smallest concentration of oxytocin (0.2 mu. ml-1). Prior exposure of the tissue to droperidol sensitized the muscle to oxytocin.

Isolation of di-N-2-propylpentyl phthalate from human urine

A higher percentage of di-N-2 propylpentyl phthalate isolated from the urine of the normals and a lower quantity in the patients suffering from Eales' disease accompanied with the occurrence in patients of another compound which is also most likely a phthalate ester has been correlated with the Eales' disease.

Amoxycillin injection in the treatment of pyogenic meningitis in children

An open trial of the use of amoxycillin injection in the treatment of pyogenic meningitis in children showed similar results to previous trials here of penicillin-chloramphenicol combinations. It is felt that, in developing countries at least, treatment of pyogenic meningitis in children should be with the latter combination, but where rapid and accurate bacteriology is available amoxycillin may be valuable non-toxic alternative to chloramphenicol with similar activity to ampicillin.

Changes in the Strength of Lettuce Endosperm during Germination

The forces required to puncture intact lettuce (Lactuca sativa) seed and pericarp, endosperm and embryo were measured by the Instron Universal Testing Machine. It required about 0.6 newton to puncture the endosperm in seeds imbibed in the dark at 6, 12 and 24 hours. Endosperm of seeds imbibed in the light or in dark with gibberellic acid required about 4.2 newtons at 6 and at 12 hours and only about 0.15 newton at 24 hours. Forces required to puncture embryo at all treatments and times remained constant at about 0.3 newton. Changes in the strength of the endosperm do not appear to be related directly to protrusion of the radicle.

Empyema in children in tropics

Thirty-six cases of empyema were diagnosed in children over a two year period, giving an overall incidence of 0.11% of the total hospital admissions. Many of them had measles bronchopneumonia and most were malnourished. 16 children had penicillin resistant staphylococcal infection. 29 of them were treated with closed tube drainage. Thirteen died during the course of treatment, the majority within three days of admission. The rest were followed up over a period of up to six months and showed good recovery. Six of these patients developed pneumothorax during the course of treatment. Various combinations of Ampicillin, Cloxacillin, Gentamycin and Cotrimoxazole parenterally were used. Supportive treatment with blood transfusion was found to be beneficial.

Intra- thecal antitetanus serum in the management of tetanus neonatorum

Eleven neonates have treated with intra-thecal antitetanus serum in addition to other standard measures. Five survived. The results were judged promising.