Cerebral vasospasm and ultrastructural changes in cerebral arterial wall. An experimental study

✓ Subarachnoid hemorrhage (SAH) was produced experimentally by injecting normal dog's blood as well as reserpinized dog's blood into the chiasmal cistern of the dog. The following observations were made: 1) After SAH with normal dog's blood, the intima of the basal truncal arterial wall showed some or all of such ultrastructural changes as appearance of vacuoles and dense bodies in endothelial cells, detachment of endothelial cells, appearance of intimal cells, and intimal thickening. The changes first appeared 2 hours after SAH, culminated at 3 to 7 days after SAH, and persisted up to 1 month after SAH. 2) After SAH with normal dog's blood, the media of the basal truncal arterial wall showed some or all of such ultrastructural changes as moth-eaten contour of muscle cells, appearance of intracytoplasmic vacuoles and dense bodies, appearance of cell debris, enlargement of interstitial space, and appearance therein of dense particles. These findings, which, in short, are to be expressed as myonecrosis and its repairing process, first appeared 2 hours after SAH, culminated at 1 to 4 months after SAH, and persisted up to 1 year after SAH. 3) Three and 5 days following SAH with reserpinized dog's blood, ultrastructural findings of the intima and media of the basal truncal arterial wall were entirely normal.

On the basis of the above findings, it was concluded that the ultrastructural changes in the cerebral arterial wall observed after SAH with normal dog's blood occurred as a consequence of vasospasm. The possibility that late spasm, in turn, might be facilitated by myonecrosis, could not be denied.

Concealed (proximal) Wenckebach phenomenon with distal 2:1 exit block in the ectopic-ventricular junction

The findings in two patients with interpolated ventricular extrasystoles showing 2:1 exit block are reported. In these patients the blocked impulses appear to penetrate into the ectopic-ventricular junction (or reentrant pathway) to a varying extent, and the coexistance of a distal 2:1 exit block and a proximal (concealed) Wenckebach phenomenon in the ectopic-ventricular junction is suggested.

Administration of prostaglandin F2alpha for the recovery of fertilized eggs from the vaginas of rabbits

Nonsurgical recovery of fertilized eggs from the vaginas of prostaglandin F2alpha (PGF2alpha)-treated rabbits was attempted. Eighty-two eggs were collected by the vaginal washing method, and the earliest egg was recovered 20 hours after mating. Twenty eggs recovered vaginally 24 to 107 hours after mating were transferred to six synchronized, pseudopregnant rabbits to test the viability of the eggs; four newborns, two fetuses, and one implantation site were obtained. These results indicate that some viable eggs are discharged into the vaginas of rabbits treated with PGF2alpha.

Origin of sequence heterogeneity of the small subunit of fraction 1 protein from Nicotiana tabacum

The partial amino acid sequences of the small subunit of Fraction 1 protein from N. sylvestris, N. tomentosiformis and N. tabacum were determined. The sequence of N. sylvestris is NH2. Gln-Val-Trp-Pro-Pro-Ile-Asn-----Tyr COOH. In the sequence up to the 7th amino acid and C-terminus, differences were only found at the 6th position in the three species, where N. sylvestris and N. tomentosiformis show Ile and Tyr, respectively. N. tabacum show both Ile and Tyr in almost equal amount at this position. These results confirmed a previous hypothesis that N. tabacum had been evolved through the hybridization of N. sylvestris and N. tomentosiformis.

Cystic goiter with squamous-cell metaplasia--case report and comment on origin of squamous-cell cyst

A 53-year-old woman with a left unilocular cystic goiter of the size of a small orange was reported. Approximately four-tenths of the innter surface was lined with several layered squamous epithelium with few follicles remaining. A gradual metaplastic transition from the follicular epithelium to the flattened cuboidal and to the squamous epithelium was observed. The ultimobranchial body has been understood to be a possible origin of an entirely squamous cell cyst of the thyroid, three of which have been reported. The difference between the ultimo-branchial and metaplastic origins will be discussed, and a new designation-primary (ultimo-branchial) and secondary (metaplastic) squamous-cell cyst will be proposed.

Origin of Nicotiana tabacum detected by primary structure of fraction I protein

Nicotiana tabacum is believed to have arisen after hybridization of Nicotiana sylvestris with a species in the Tomentosae section of the genus Nicotiana. Recent biochemical experiments have confirmed the conclusions from previous cytogenetic studies that N. sylvestris was the maternal parent and have indicated that Nicotiana tomentosiformis was the paternal parent. However, these studies did not take into account the possibility that a new species of Nicotiana, called K-12, discovered in South America in 1968, could also have been one of the parents. Fraction I proteins were purified from N. tabacum and its putative progenitors, and separated into large and small subunits. Chymotryptic peptides of each subunit were analyzed by ion exchange column chromatography with a gradient elution system. Among 38 resolved peaks of the large subunits, 2 peaks were found to be different among the putative species. Since only N. sylvestris showed an identical chromatogram with N. tabacum, N. sylvestris was concluded to be the maternal progenitor, as the genetic information for the large subunit of Fraction I protein was known to be inherited by the cytoplasmic mode. On the other hand, the small subunit of Fraction I protein is inherited by the Mendelian mode and therefore N. tabacum, an allopolyploid, could be expected to contain two types of small subunits, one derived from N. sylvestris and the other from a paternal progenitor. N. sylvestris lacks two of the 25 chymotryptic peptides of the small subunit of N. tabacum. Among 3 putative paternal progenitors, these two peaks appeared only in N. tomentosiformis, but not in Nicotiana otophora or K-12. Thus, N. tomentosiformis was concluded to be a paternal progenitor of N. tabacum. The conclusion was verified by comparing chymotryptic peptides of small subunits from three amphidiploids of N. sylvestris crossed with N. tomentosiformis, N. sylvestris crossed with N. otophora snd N. sylvestris crossed with K-12. The analytical results showed that only the progeny of N. sylvestris crossed with N. tomentosiformis contained the same small subunits as N. tabacium.

Simultaneous determinations of oestradiol-17 beta, progesterone and luteinizing hormone in the plasma during the ovulatory cycle of the hen

Simultaneous determinations of plasma levels of oestradiol-17beta, progesterone and luteinizing hormone (LH) during the ovulatory cycles of hens were performed using radioimmunoassay techniques without chromatography. Blood samples were collected from the wing vein of 7 hens with regular ovulatory cycle at intervals of 1, 2 or 4 h throughout 36 h starting 24-25 h before the second egg (C-2) ovulation of the clutch and ending 11-12 h after C-2 ovulation. The oestradiol-17 beta level of the plasma during the ovulatory cycle varied from 50 pg/ml to 250 pg/ml. The value was high 24 h before ovulation and decreased until 10 h before ovulation, then increased and reached a peak 4-5 h before ovulation, when it started to decrease again until 12 h after ovulation. The plasma levels of progesterone varied from 1 ng/ml to 6 ng/ml, and reached a peak 4-6 h before ovulation. The plasma LH value varied from 1 ng/ml to 4 ng/ml, and the changes in the levels corresponded well with that of progesterone, also showing a coincident peak.

Second degree entrance block in intermittent ventricular parasystole

In a 21-year-old healthy man, there may be a second degree entrance block occasionally of 2:1 nature resulting in intermittent ventricular parasystole. The refractory period of the ventricular-ectopic (V-E) junction in this case was markedly longer than the ventricular muscle except the V-E junction, but much shorter than the whole length of the parasystolic cycle.

Steroidogenesis in vitro by the ovarian tissue of the domestic fowl (Gallus domesticus)

Ovaries excised from 5- and 7-month-old laying hens were homogenized. The homogenates were incubated separately with 4-14C-labelled pregnenolone, progesterone, 17α-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, oestrone and oestradiol, and [7-3H]17αhydroxypregnenolone in the presence of NAD+ or NADPH under aerobic conditions. The homogenates synthesized progesterone, 17αhydroxyprogesterone, 17α-hydroxypregnenolone, dehydroepiandrosterone, androstenedione, testosterone, pregnanedione, 17α-hydroxy-5β-pregnane3,20-dione, 5β-androstane-3,17-dione, 19-hydroxyandrostenedione, 19hydroxytestosterone, oestrone, oestradiol and other minor metabolites. However, the rates for the conversion of androstenedione to oestrone and that of testosterone to oestradiol were low, and after 120 min incubation, the yields were 3·0 and 1·2%, respectively. The results indicate possible involvement of metabolic pathways both from Δ5-C21 steroid to Δ4-C21 steroid and from Δ5-C21 steroid to Δ5-C19 steroid in the formation of androgen by the ovary of the domestic fowl.

In vitro metabolism of steroid hormones by chicken brain

The brains of 14-month-old White Leghorn cocks were homogenized, fractionated by differential centrifugation, and used as enzymatic materials. When [4-14C]pregnenolone was incubated with the brain homogenate, the substrate was recovered without conversion. After incubation of [4-14C] progesterone with the brain homogenate, it was converted to 5α-pregnanedione and 3α-hydroxy-5α-pregnan-20-one. When [4-14C]17α-hydroxyprogesterone was incubated with the brain homogenate, it was metabolized to androstenedione, 3α, 17α-dihydroxy-5α-pregnan-20-one and 17α,20α-dihydroxy-4-pregnen-3-one. [4-14C] Androstenedione was metabolized to 5α-androstanedione, testosterone, androsterone, epiandrosterone and 5α-androstanediol; and [4-14C]testosterone was metabolized to androstenedione, 5β-dihydrotestosterone and 5β-androstanediol in the chicken brain. The enzymatic pattern in the brain of cocks was characterized by high activities of the 17β-hydroxysteroid dehydrogenase. Δ4-5β- and Δ5-5β-hydrogenase which acted on both C19- and C21-steroids, but was lacking in Δ5-3β-hydroxysteroid dehydrogenase associated with the Δ5a-Δ4isomerase, and 17α-hydroxylase.

Pathways for androgen synthesis in vitro by the testes of Japanese quail (Coturnix coturnix japonica)

The microsomal fraction of testicular tissue from Japanese quail (Coturnix coturnix japonica) was incubated with 4-14C-labelled pregnenolone, progesterone, 17α-hydroxyprogesterone, androstenedione, dehydroepiandrosterone and testosterone and [7-3H]17α-hydroxypregnenolone in a medium containing either NAD or NADPH. The metabolic products were identified by their mobilities on thin-layer chromatograms, derivative formation after oxidation and acetylation of the metabolites, and recrystallization to constant specific activity.

Three pathways for testosterone formation by the testes are suggested by the results: the first via progesterone, 17α-hydroxyprogesterone and androstenedione; the second via 17α-hydroxypregnenolone, dehydroepiandrosterone and androstenedione; and the third via 17α-hydroxypregnenolone, dehydroepiandrosterone and androst-5-ene-3β,17β-diol.