Expression of intermediate filaments and other special markers by testicular germ cell tumors. With reference to embryogenesis

Distribution of intermediate filament proteins (IFs) and several special markers was studied in 39 testicular germ cell tumors and 8 embryos and foetuses. The similarity and difference between development of germ cell tumor and embryogenesis were immunohistochemically investigated. Seminoma and embryonal carcinoma, as tumoral counterparts of undifferentiated germ cells, were characterized by little IF expression. This study revealed that the maturing and differentiating process in germ cell tumor is different from normal embryonal development and the tumor cells showed leaping maturing steps in tumorigenesis. Immunostaining for IFs helped to discover the further differentiation occurring in embryonal carcinoma and to demonstrate heterogeneous elements in non-seminoma germ cell tumors, which sometimes might not be apparent by light microscopical observation of H&E staining section. According to the findings, two patterns in mixed germ cell tumors are suggested; i.e., combined and diffuse types. The mechanism of tumorigenesis of the two types is supposed to be different. Clinically, the prognosis of most patients with testicular germ cell tumor is fairly good because of the improved chemotherapies that are dependent on histological diagnosis.

Haemodialysis as a model for studying endogenous plasma DNA: oligonucleosome-like structure and clearance

The rate of clearance of extracellular plasma DNA in man has important implications for pathogenetic mechanisms in systemic lupus erythematosus (SLE), as well as for certain other clinical states. Present knowledge of this parameter is derived exclusively from studies of injected, naked DNA in animals. Recent information indicates that the physiologic form of plasma DNA in SLE is that of oligonucleosome-like molecules rather than of naked DNA and consists of multimeric complexes of DNA bound to histone, probably arising from an apoptotic process. In order to study the rate at which these oligonucleosome-like complexes are removed from plasma and to do so in man rather than experimental animals, we exploited the observation that during haemodialysis large amounts of DNA are released, apparently within the dialysis coil, into the patient's plasma. Since this release appears to cease promptly with termination of the procedure, it offered the potential for estimating the rate of removal of such DNA from human plasma. Moreover, if that DNA, as postulated, were shown to possess an oligonucleosome-like structure resembling that found endogenously in human SLE, the relevance of such information to the human disease state would be further enhanced. The present results support the conclusion that DNA released into plasma during haemodialysis possesses such an oligonucleosome-like structure. The plasma half-life of that DNA in man was found not to exceed 4 min. The highly dynamic state thus implied for extracellular endogenous plasma DNA in man has important implications for pathogenetic mechanisms dependent on dsDNA in SLE. Moreover, individuals undergoing chronic haemodialysis, who are thereby exposed to a very large cumulative amount of such DNA, might serve as models for studying its long-term sequelae.

[A study on measles vaccination rate and its antibody level in children aged 12-24 months in Guangxi, 1989]

This report described the measles vaccination rate (MVR) as well as its HI antibodies of 1842 children aged from 12 to 24 months. The MVR was 99.57% but HI positive rate was only 83.50%. HI of 298 target children still remained negative. Among them, 6 children were unvaccinated and others vaccinated. The HI negative rate reached 16.50% The HI positive rate was higher in the target children who lived in the area with convenient transportation and relatively low atmospheric temperature, and who received measles vaccine at the age of 8 months or more. Otherwise, the HI positive rate was lower. So some suggestions were proposed that the vaccination season, age of vaccine, increasing vaccine dosage should be considered carefully before measles vaccination session had arranged.

cGMP-dependent protein kinase regulation of a chloride channel in T84 cells

Chloride channels at the apical membrane of intestinal epithelial cells are involved in the excessive fluid secretion in diarrhea and diminished secretion in cystic fibrosis (CF). Diarrhea induced by heat-stable toxin from Escherichia coli is associated with elevated guanosine 3',5'-cyclic monophosphate (cGMP) in intestinal epithelial cells, but it is unknown whether chloride secretion is regulated by cGMP directly or via cGMP-dependent protein kinase (PKG). Single-channel recordings (inside-out excised patches) from the apical membrane of T84 cells reveal a 10-pS chloride channel with a linear current-voltage relationship, which is opened when an endogenous membrane-bound PKG is activated with ATP (1 mM) and cGMP (100 microM). Soluble PKG (200 nM) isolated from bovine lung, added to the intracellular face of patches, also opens this channel. No activation occurs with Ringer solution alone or only ATP or cGMP. Addition of nonhydrolyzable forms of ATP (AMP-PNP, 1 mM) or a combination of ATP, cGMP, plus H-8 (5 microM), an inhibitor of PKG, also does not stimulate the channel. The catalytic subunit of adenosine 3',5'-cyclic mono-phosphate-dependent protein kinase (PKA, 200 nM, with 1 mM ATP) activates a channel with similar characteristics. The 10 pS channel has a PNa/PCl ratio of 0.06, an anion selectivity of Br- (1.2) greater than Cl- (1.0) greater than I- (0.8) greater than F- (0.4), and a low affinity for the chloride channel blockers, 4,4-dinitrostilbene-2,2-disulfonic acid and 5-nitro-2-(3-phenylpropylamino)benzoic acid.(ABSTRACT TRUNCATED AT 250 WORDS)

Contraction of glycerinated rabbit slow-twitch muscle fibers as a function of MgATP concentration

We have measured the isometric tension and force-velocity relationships of glycerinated rabbit slow-twitch semimembranosus muscle as a function of MgATP concentration ([MgATP]) and have compared the results with those obtained previously from fast-twitch psoas muscle. We find that isometric tension decreases as [MgATP] increases. The magnitude of the decrease is not as great as observed in psoas. Maximum shortening velocity (Vmax) exhibits classical Michaelian saturation behavior with respect to [MgATP] with a Michaelis constant (Km) for half-maximal velocity of 18 microM and a value at saturating [MgATP] of 0.6 muscle lengths/s. Similar values were observed in fibers from soleus, another slow-twitch muscle. The corresponding values in rabbit psoas muscle are 150 microM and 1.6 lengths/s. Compared with psoas, in semimembranosus muscle Km decreases by a factor of approximately 10, whereas Vmax decreases by about a factor of 3. Thus, although in a nonphysiological regime, at low [MgATP], a "fast" muscle actually has a lower shortening velocity than a "slow" muscle.

Renewal and proliferation of spermatogonia during spermatogenesis in the Japanese quail, Coturnix coturnix japonica

Four different types of spermatogonia were identified in the seminiferous tubules of the Japanese quail: a dark type A (Ad), 2 pale A types (Ap1 and Ap2), and a type B. A model is proposed describing the process of spermatogonial development in the quail. The Ad spermatogonia are considered to be the stem cells. Each divides to produce a new Ad spermatogonium and a Ap1 spermatogonium during Stage IX of the cycle of the seminiferous epithelium. An Ap1 spermatogonium produces two Ap2 spermatogonia during Stage II of the cycle, Ap2 spermatogonia produce four type B spermatogonia during Stage VI of the cycle, and type B spermatogonia produce eight primary spermatocytes during Stage III of the cycle. Consequently, 32 spermatids can result from each division of an Ad spermatogonium. Spermatogonial development in the quail differs from the process described in mammals in that there are fewer mitotic divisions and they are all synchronized with the cycle of the seminiferous epithelium. It is suggested that the fewer mitotic divisions explain why a smaller area of the seminiferous tubule is occupied by a cellular association in the quail than in mammals like the rat, ram and bull. The duration of spermatogenesis from the division of the Ad spermatogonia to sperm release from the seminiferous epithelium was estimated to be 12.77 days.

Nosocomial outbreak of scabies

Scabies is a common infestation caused by the human itch mite Sarcoptes scabiei. Small outbreaks in communities or hospitals are not uncommon, but are rarely documented. In this paper, we report on a nosocomial outbreak of scabies originating from a patient with Norwegian scabies at the Intensive Care Unit in Taiwan Provincial Tainan Hospital. Twenty-nine individuals including four inpatients and 25 hospital personnel were involved. The diagnosis was based on history, clinical findings or a positive skin scraping. Unfamiliarity with the clinical manifestations delayed the diagnosis and the highly contagious nature of Norwegian scabies precipitated this outbreak. Early initiation of effective control measures with extensive therapeutic and prophylactic treatment of all contacts resulted in successful eradication of the outbreak.

Purification and Molecular and Immunological Characterization of a Unique Phosphoribulokinase from the Green Alga Selenastrum minutum

A unique phosphoribulokinase (ADP:D-ribulose 5-phosphate 1-phosphotransferase, EC 2.7.1.19) has been purified to homogeneity from the green alga Selenastrum minutum. The enzyme has a native molecular mass of about 83 kilodaltons and a native isoelectric point of 5.1. The enzyme consists of two different-sized subunits of 41 and 40 kilodaltons, implying that it is a heterodimer. This is the first report of a eukaryotic heterodimeric phosphoribulokinase. The in vivo existence of two nonidentical subunits of S. minutum phosphoribulokinase was confirmed by western blot analysis of crude protein extracts from trichloroacetic acid-killed cells. These two subunits were immunologically similar, as rabbit immunoglobulin G affinity purified against the 41 kilodalton subunit of S. minutum phosphoribulokinase (PRK) cross-reacts with the 40 kilodalton subunit and vice versa. Antibodies against S. minutum phosphoribulokinase also cross-react with the spinach enzyme. NH(2)-terminal sequencing revealed that the two S. minutum PRK subunits shared a considerable degree of structure homology with each other and with the enzymes from spinach and Chlamydomonas reinhardtii, but not with PRK from Rhodobacter sphaeroides. There are, however, differences between the NH(2)-terminal amino acid sequences of the two S. minutum PRK subunits, that imply that they are the products of separate genes or products of two different mRNAs spliced from a single gene.

Ultrastructure of the Genital Duct Epithelium of the Male Port Jackson Shark, Heterodontus-Portusjacksoni

The genital ducts of Heterodontus portusjacksoni are lined by a ciliated epithelium. In the ductuli efferentes the epithelium is low and contains numerous intraepithelial leucocytes which often contain large dense bodies. All epithelial cells are ciliated and are characterised by apical vesicles, vacuoles and glycogen granules, some rough endoplasmic reticulum, dense bodies and lipid droplets, and a Golgi apparatus. The initial segment of the ductus epididymidis is lined by a very tall epithelium of ciliated and non-ciliated cells. The non-ciliated cells contain numerous apical vesicles, a large Golgi apparatus and numerous mitochondria and secretory granules in close association with an extensive endoplasmic reticulum. The terminal segment of the ductus epididymidis is lined by a low columnar epithelium. A proximal region, occupying part of the head of the epididymis, is similar to the epithelium in the ductuli efferentes. Distally, all the epithelial cells are ciliated. They are characterised by considerable dilated endoplasmic reticulum, a Golgi apparatus, apical vesicles, and numerous mitochondria and secretory granules. The secretory tubules of Leydig's glands are lined by a very tall epithelium with non-ciliated cells containing extensive, dilated, rough endoplasmic reticulum, a large Golgi apparatus, and numerous mitochondria and secretory granules. The significance of the structural differentiation of the duct is discussed in relation to the evolution of the mammalian epididymis.

Comparisons of long-term effects between converting enzyme inhibitors and conventional therapy in treating mild to moderate hypertension

A group of consecutive 180 veteran patients with mild to moderate essential hypertension were chosen to participate in clinical antihypertensive trial for the purpose of defining the role of converting enzyme inhibitors and renin-angiotensin-aldosterone system in the management of mild to moderate hypertension patients. After a two-week placebo period, these patients were randomly assigned to regimens of converting enzyme inhibitors (enalapril or captopril with or without diuretics) or conventional therapy (diuretics with or without traditional vasodilators with or without beta-blockers). Each patient was regularly followed up every two weeks and doses were added until the diastolic blood pressure was equal to or lower than 90 mmHg. After 1 year of follow-up, only 162 patients completed the study. All high blood pressure was significantly reduced by these three regimens, but no significant difference of blood pressure control was noted. The mean left ventricular ejection fraction increased from 55.9 +/- 6.2 to 57.5 +/- 5.3% in captopril group (P less than 0.05, n = 59) and from 54.8 +/- 6.8 to 57.2 +/- 5.8% enalapril group (P less than 0.01, n = 53), in contrast to the insignificant change in control group (n = 50) (56.5 +/- 7.7 to 56.6 +/- 5.9%). The exercise duration also significantly increased only in converting enzyme inhibitors group (P less than 0.01). Furthermore, the plasma aldosterone level was significantly reduced by converting enzyme inhibitors therapy, whereas conventional therapy had no beneficial effect (P less than 0.01). Furthermore, the plasma aldosterone level was significantly reduced by converting enzyme inhibitors therapy, whereas conventional therapy had no beneficial effect (P less than 0.001). Concomitantly, antidiuretic hormone and plasma norepinephrine levels were also significantly reduced by converting enzyme inhibitors. In addition, converting enzyme inhibitors had a favorable trend to affect the metabolism of lipid in contrast to the conventional therapy. These results show that a first-step treatment of hypertension with converting enzyme inhibitors permits better left ventricular function and improves exercise tolerance by way of renin-angiotensin-aldosterone system inhibition. Thus, converting enzyme inhibitors might be suggested as the first step regimen in the treatment of hypertension.

Argyrophilia in ovarian serous tumors. A comparative study in 127 epithelial ovarian tumors

The distribution of argyrophil cells in epithelial ovarian tumors was studied in 127 cases. The results showed that not only mucinous tumors and endometrioid tumors contained argyrophil cells, but also some serous tumors expressed argyrophilia. 31% of serous tumors including 40% of serous adenocarcinomas contained variable numbers of argyrophil cells. Argyrophilia has been demonstrated in mucinous tumors, endometrioid tumors and Brenner tumors before. However, this is the first time the presence of argyrophilia in serous tumors has been noticed. Moreover, the argyrophil cells in 5 serous carcinomas showed reactivity with Neuroendocrine (chromogranin A) antibody but not with serotonin. The expression pattern of argyrophilia in the serous tumors was different from that of the mucinous tumors; in the former, argyrophil granules appeared in apical portions or throughout the cytoplasm of single or clustered cells. In addition, the argyrophilia in some serous tumors and endometrioid tumors decreased after diastase digestion. Ultrastructurally, no typical neurosecretory granule was found in the argyrophilic serous tumors. The findings in this study suggest that argyrophilia could be quite frequently found in ovarian epithelial tumors and in itself is not a very specific differential characteristic of carcinoid tumors. The argyrophilia found in a variety of epithelial ovarian tumors might lend additional support to the histogenesis and close relationship between the common epithelial tumors of the ovary.

The efficacy of early continuous positive airway pressure therapy in patients with acute cardiogenic pulmonary edema

Although continuous positive airway pressure (CPAP) therapy using a face mask is known to improve oxygenation, the intrapulmonary shunt reduction remains unsettled. Our study was designed to explore this issue. From 1985 to 1987 80 patients with acute cardiogenic pulmonary edema were randomly chosen to receive either serial CPAP therapy or high-flow face mask oxygen therapy without CPAP (control) for the purpose of evaluating the efficacy of CPAP therapy. After screening for exclusion, only 55 patients were included in the first 3-hour investigation period. PaO2 in the CPAP group showed a significant increase by the end of the initial study; whereas intrapulmonary shunt and alveolar-arterial oxygen tension gradient AaDO2 revealed simultaneously a significant reduction. Conversely, neither PaO2 nor intrapulmonary shunt (or AaDO2) in the control group demonstrated any significant beneficial changes. As for cardiovascular function, only the CPAP therapy achieved a significant reduction in rate pressure product in contrast to the control (face mask) therapy alone. In terms of therapeutic failure, 10 patients in the control group failed. However, in the CPAP group only 5 patients had failed at the end of the first 3-hour study period. Overall, the cumulative therapeutic failure rate was 28% in the CPAP group and 60% in the control group during a 6-hour observation study. However, there was no significant difference between the two groups in 24-hour hospital mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Enalapril in congestive heart failure: acute hemodynamic and neurohumoral evaluation and short-term follow-up

The acute efficacy of rapid loading of oral long-acting enalapril in congestive heart failure remains to be established. We evaluated the efficacy of this treatment modality in 22 patients with chronic congestive heart failure N.Y.H.A. functional class ranging from II-IV with Creatinine level less than 2 mg/dl. Following hemodynamic evaluation, there was significant favorable change in the left ventricular functional curve. Moreover, acute hemodynamic assessment showed a significant reduction in pulmonary capillary wedge pressure from 19.2 +/- 4.8 to 17.2 +/- 4.7 mmHg (p less than 0.005) and an increases in stroke volume index from 28.3 +/- 9.2 to 33.1 +/- 7.5 ml/m (p less than 0.005). After rapid enalaprilization, blood pressure fell from 127 +/- 21/78 +/- 15 to 108 +/- 21/68 +/- 15 mmHg (p less than 0.005), systemic vascular resistance from 1725 +/- 602 to 1370 +/- 376 dyne.sec.cm-5 (p less than 0.05) and pulmonary vascular resistance from 262 +/- 19 to 218 +/- 65 dyne.sec.cm-5 (p less than 0.05). Cardiac index rose significantly from 2.43 +/- 0.62 to 2.60 +/- 0.50 l/min/m2 (p less than 0.05). In terms of neurohumoral assessments, there was a significant inhibition of the renin-angiotensin-aldosterone system. Aldosterone fell from 21.3 +/- 13.4 to 9.4 +/- 8.0 ng/dl and plasma renin activity rose from 3.3 +/- 4.6 to 11.3 +/- 11.0 ng/nl/hr (p less than 0.005). Plasma norepinephrine and epinephrine levels were found to have significant reduction in addition to antidiuretic hormone concentration. During short-term trial, left ventricular ejection fraction was significantly elevated from 27.5 +/- 6% to 32.8 +/- 10.8% (p less than 0.005). Thus, this limited study clearly demonstrates the rapid administration of enalapril not only achieves inhibition of renin-angiotensin-aldosterone system but also reduces preload and afterload significantly in the failing heart. We conclude that rapid enalaprilization is an effective methodology which still needs meticulous attention, providing significant hemodynamic and symptomatic benefits in patients with chronic congestive heart failure.

Comparison of enalapril and conventional vasodilator therapy in patients with chronic congestive heart failure

The aim of this study was to investigate the role of the renin-angiotensin-aldosterone system during anti-heart failure treatment with additional enalapril versus conventional vasodilator therapy (hydralazine + sorbitrate) and to assess whether or not enalapril can be suggested as the preferential vasodilator therapy in patients with chronic congestive heart failure. Over a 2.5-year period, 120 patients (New York Heart Association II-IV, creatinine less than or equal to 2.0 mg/dl) were enrolled in the study and randomly assigned to receive enalapril or hydralazine and sorbitrate therapy in addition to optimal digitalis and diuretics administration. At the end of a one-year followup, there was a tendency for mortality to be lower in the enalapril[correction of enlapril] group (4 cases) compared to the conventional group (9 cases), but the difference was not significant (p = 0.21). Both groups showed similar increases in plasma renin activity. The plasma aldosterone level decreased significantly in the enalapril group (p less than 0.005); whereas it rose significantly in the conventional group (p less than 0.005). The plasma norepinephrine level of the enalapril group fell significantly when compared with the conventional group. Thus, enalapril therapy achieved better reduction in the activating sympathetic system (p less than 0.0001). Reduction in the anti-diuretic hormone level was also found to be highly significant in the enalapril group, whereas no difference was seen in the conventional group. Furthermore, the serum creatinine level and blood urea nitrogen remained unchanged in the conventional group; whereas both were demonstrated to be reduced significantly in the enalapril group at a 1-year follow up.(ABSTRACT TRUNCATED AT 250 WORDS)

Intracellular heterogeneity in mitochondrial membrane potentials revealed by a J-aggregate-forming lipophilic cation JC-1

By using a potential-dependent J-aggregate-forming delocalized lipophilic cation, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine++ + iodide (JC-1), we find that membrane potentials across mitochondria in a living cell can be heterogeneous. Remarkably, even within a long contiguous mitochondrion, regional heterogeneity in membrane potentials appears to be possible.

Replication of ocular isolates of human adenovirus is serotype-dependent in rabbit corneal organ culture

The goal of the present in vitro study was to determine the ability of unadapted human adenoviral ocular isolates to replicate in the rabbit cornea. Rabbit corneas grown in organ culture (24 well plate) were inoculated topically with 50 microliters (5 x 10(5) pfu) of different ocular adenoviral serotypes (ATCC and clinical isolates). Control wells (no cornea present) were inoculated in a similar fashion. Viral replication was determined by serial aliquots titrated on A549 cells. We demonstrated sustained viral replication over time of all isolates (100%) of Ad1, 2, 5, 6, 8, 9, 11 and 37 tested. No isolates (0%) of Ad3, 7A, 19, and 4 demonstrated replication in our model. Peak titers varied among successful serotypes from 10(2) pfu/ml (Ad11) to 10(5) PFU/ml (Ad5), and among different isolates of a given serotype. We conclude that the ability of unadapted human Ad serotypes to replicate in rabbit corneas was serotype-dependent, and that subgroup C (Ad1, 2, 5, and 6) appeared to be the most successful subgroup.

Hemodynamic response to BMI model PIAB catheter

Using the BMI model PIAB catheter designed and produced by our laboratory, we carried out serial animal experiments to evaluate its hemodynamic effects in goats. The animal experiments and comparison tests indicated that BAPDP = 24, PSP = 22; BAEDP = 8, EDP = 14; BAPSP = 20, PSP = 22. The various hemodynamic parameters of our PIAB catheter are equivalent to or better than those of imported products. But the price of our PIAB catheter is much lower than that of foreign products. It has been used in some hospitals, showing satisfactory results.

S-100 protein in ovarian tumors. A comparative immunohistochemical study of 135 cases

The distribution of S-100 protein in 135 ovarian tumors, of which 127 were epithelial, was investigated using the immunoperoxidase method. S-100 protein has been demonstrated previously in tumors of various origins. The present study further revealed its characteristic distribution in common epithelial tumors of the ovary. S-100 protein was present in 69% of serous tumors (benign, 50%; borderline, 100%; malignant, 71%), as well as in the serous elements of serous & mucinous mixed tumors (30%). S-100 protein was also demonstrated in 25% of clear cell carcinomas and 29% of endometrioid carcinomas. Interestingly, none of the mucinous tumors were positive for S-100 protein. In addition, the expression of S-100 protein by epithelial ovarian tumors was compared with that of CA 125 and carcinoembryonic antigen (CEA). The distribution of S-100 protein was similar to that of CA 125, since both antigens were frequently present in serous tumors, although their expression patterns were different. On the other hand, S-100 protein-positive cases were almost negative for CEA or vice versa. Our observations indicate that demonstration of S-100 protein in common epithelial tumors of the ovary and comparison of S-100 protein distribution with that of CA 125 and CEA may further clarify the characteristics of common epithelial tumors of the ovary.

Evidence for intraluminal Ca++ regulatory site defect in sarcoplasmic reticulum from malignant hyperthermia pig muscle

Malignant hyperthermia (MH) is a pharmacogenetic disease of humans and various animal species that predisposes to a life-threatening, anesthetic agent-induced syndrome. MH is thought to be a consequence of abnormal, sustained increases in myoplasmic Ca++ and sarcoplasmic reticulum (SR) membranes from MH muscle have been shown to have a Ca++ release channel defect. In the present study we have tested a hypothesis that the abnormal Ca++ release mechanism in MH can be expressed when Ca++ is loaded in the presence of pyrophosphate. SR membrane vesicles isolated from normal and MH pig muscle were loaded with Ca++ in the presence and absence of pyrophosphate until Ca(++)-induced Ca++ release occurred. Under both circumstances the threshold amount of Ca++ loaded until Ca++ release occurred was lower in the SR from MH pig skeletal muscle. This difference in amount of Ca++ preload is not explained by results obtained comparing rates of Ca++ uptake, number of ryanodine binding sites or the amounts of calsequestrin among SR vesicles from MH and normal muscle. We conclude from this study that use of pyrophosphate for Ca++ loading does not ablate the abnormal Ca++ release in SR from MH muscle, suggesting the study can be done on small amounts of SR from biopsied human muscle. The data also suggest that abnormality in an intraluminal, low affinity Ca++ binding site regulating Ca++ release occurs in the SR membrane of MH pig muscle.

Atypical lipoleiomyoma of the uterus

A case of uterine atypical lipoleiomyoma in a 55-year-old obese woman is described. Histologically it was composed of atypical smooth muscle tissue and adipose tissue, as proved by immunohistochemical staining and ultrastructural study. Moreover, these studies revealed a transition from tumor smooth muscle cells to lipocytes. The features of this tumor suggest that at least some lipoleiomyomas result from lipomatous metaplasia of leiomyoma. Lipoleiomyoma is a rare lesion of the uterus, and the present tumor with an atypical leiomyomatous appearance is the first reported case of its kind. A review of previous case reports, together with the condition of this patient, revealed that patients with lipoleiomyoma are often overweight and menopausal, and have a high incidence of gallbladder disease.

Spatial arrangement of the stages of the cycle of the seminiferous epithelium in the Japanese quail, Coturnix coturnix japonica

The spatial arrangement of the stages of the cycle of the seminiferous epithelium of the Japanese quail was investigated by preparing three-dimensional reconstructions of a seminiferous tubule from each of 3 quails. It was found that the stages were not distributed at random, but were arranged in a wave which spiralled helically along a seminiferous tubule. Adjacent stages in space were always adjacent numbers in the cycle of the seminiferous epithelium. Complete spermatogenetic waves were found in which all 10 stages of the cycle were in sequential order. However, in most waves the sequential order of stages was disturbed by the occurrence of modulations. The area of a cellular association varied from 4600 to 41,600 microns 2 with a mean +/- s.e.m. (3 animals) of 17,902 +/- 2614 microns 2. The number of Sertoli cells involved in an association ranged from 4 to 35, with a mean +/- s.e.m. (3 animals) of 13.5 +/- 2.8. The findings support our earlier suggestion that the kinetics of spermatogenesis in the quail are fundamentally similar to the pattern which has been described for mammals.

Cytochrome and Alternative Pathway Respiration during Transient Ammonium Assimilation by N-Limited Chlamydomonas reinhardtii

Mass spectrometric analysis of gas exchange in light and dark by N-limited cells of Chlamydomonas reinhardtii indicated that ammonium assimilation was accompanied by an increase in respiratory carbon flow to provide carbon skeletons for amino acid synthesis. Tricarboxylic acid (TCA) cycle carbon flow was maintained by the oxidation of TCA cycle reductant via the mitochondrial electron transport chain. In wild-type cells, inhibitor studies and (18)O(2) discrimination experiments indicated that respiratory electron flow was mediated entirely via the cytochrome pathway in both the light and dark, despite a large capacity for the alternative pathway. In a cytochrome oxidase deficient mutant, or in wild-type cells in the presence of cyanide, the alternative pathway could support the increase in TCA cycle carbon flow. These different mechanisms of oxidation of TCA cycle reductant were reflected by the much greater SHAM sensitivity of ammonium assimilation by cytochrome oxidase-deficient cells as compared to wild type.

Primary adenocarcinoma of the female urethra with three histologic patterns and partial AFP positivity

A rare case of adenocarcinoma of the female urethra with alpha-fetoprotein (AFP) positivity in a 52-year-old woman is reported. The tumor was papillary polypoid, localized in the posterior wall of the mid-urethra and microscopically showed three histologic components. Upon immunostaining and histochemical staining, the tumor was characterized by intestinal-type cells positive for epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA), EMA-negative and AFP-positive columnar vacuolated cells and mainly EMA-positive clear cells. On the basis of these features together with the known embryogenesis of the urethra, an endodermal origin of the tumor is suggested, possibly arising from the reserve or stem cells in the urethral mucosa. This case and its immunohistochemical features are quite unique and the histologic combination is meaningful when considering the oncogenesis and histogenesis of urethral tumors.