scholarly journals The biosynthesis of androst-16-enes in boar testis tissue

1970 ◽  
Vol 117 (3) ◽  
pp. 533-538 ◽  
Author(s):  
Tatyana Katkov ◽  
D. B. Gower
Keyword(s):  
Short Term ◽  
Fresh Tissue ◽  
Labelled Compound ◽  
Testis Tissue

1. The metabolism of [4-14C]pregnenolone to androst-16-enes has been studied in short-term incubations of boar testis tissue. With fresh tissue androsta-5,16-dien-3β-ol (8%) and 5α-androst-16-en-3β-ol (2%) were formed. Tissue that had been stored at −20°C was still capable of metabolizing pregnenolone to androsta-5,16-dien-3β-ol. 2. NADPH was essential for the formation of androsta-5,16-dien-3β-ol from pregnenolone; NADH had less activity and ATP was not necessary for the reaction. 3. [4-14C]Androsta-5,16-dien-3β-ol, prepared biosynthetically from [4-14C]pregnenolone, was shown to be converted by boar testis preparations into androsta-4,16-dien-3-one (31%) if NAD+ was present or into 5α-androst-16-en-3β-ol (4%) if NADPH was present. 4. 17α-Hydroxyandrost-4-en-3-one and 3β,17α-dihydroxypregn-5-en-20-one were considered as possible precursors for androst-16-ene formation, but both were shown to be ineffective. 5. No radioactivity was incorporated into androst-5-en-3β-ol used to trap any corresponding 14C-labelled compound formed from [4-14C]pregnenolone.

Postchemotherapy Ejaculatory Azoospermia: Fatherhood With Sperm From Testis Tissue With Intracytoplasmic Sperm Injection

2002 ◽  
Vol 20 (4) ◽  
pp. 930-936 ◽  
Author(s):  
M. N. Damani ◽  
V. Masters ◽  
M. V. Meng ◽  
C. Burgess ◽  
P. Turek ◽  
...  
Keyword(s):  
Intracytoplasmic Sperm Injection ◽  
Fertilization Rate ◽  
Nonobstructive Azoospermia ◽  
Fresh Tissue ◽  
Icsi Cycle ◽  
Small Subgroup ◽  
History Of ◽  
Fertility Potential ◽  
Late Maturation ◽  
Testis Tissue

PURPOSE: To define the success of testis sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI) in azoospermic men with a history of chemotherapy. PATIENTS AND METHODS: In a retrospective study, 23 men with ejaculatory azoospermia and a history of chemotherapy underwent TESE in a search for usable spermatozoa. In six patients cryopreserved tissue and in nine patients fresh tissue provided sperm for an ICSI cycle. Histologic analysis of the testis was performed in all patients. The presence or absence of sperm, fertilization rates with ICSI, and final outcomes of pregnancy were recorded. RESULTS: Spermatozoa were found on TESE in 15 (65.2%) of 23 men. On histopathology, the predominant pattern observed was Sertoli cell only (47.8%), followed by hypospermatogenesis (30.4%), mixed (17.4%), and late maturation arrest (4.3%). The fertilization rate was 65.2%, and ongoing/delivered pregnancies occurred in 30.8% of cycles. Six healthy boys and four healthy girls have been born to date. CONCLUSION: Men who are azoospermic and have had prior cytotoxic therapy make up a small subgroup of males with nonobstructive azoospermia. It is important to define and characterize this subgroup and better define their true fertility potential. Approximately two thirds of these men have retrievable testis sperm, which may be used with ICSI to have healthy offspring. This exciting avenue for paternity has heretofore not been available to such patients.

scholarly journals 16-Unsaturated C19 3-oxo steroids as metabolic intermediates in boar testis

1972 ◽  
Vol 128 (4) ◽  
pp. 945-952 ◽  
Author(s):  
P. J. Brophy ◽  
D. B. Gower
Keyword(s):  
Prolonged Storage ◽  
Fresh Tissue ◽  
Optimum Yield ◽  
Metabolic Intermediates ◽  
Unsaturated Alcohols ◽  
Testis Tissue

1. The formation of the two 16-unsaturated alcohols 5α-androst-16-en-3α-ol and 5α-androst-16-en-3β-ol from [5α-3H]5α-androst-16-en-3-one has been demonstrated in boar testis homogenates. 2. The optimum yield (23%) of the 3α-alcohol was obtained in the presence of NADPH, whereas that for the 3β-alcohol (74%) was obtained when NADH was the added cofactor. 3. The two alcohols were not interconvertible. 4. Prolonged storage of boar testis tissue at −20°C abolished the ability to form all androst-16-enes except androsta-4,16-dien-3-one from [4-14C]progesterone. 5. The production of 5α-androst-16-en-3-one and the two alcohols from [7α-3H]androsta-4,16-dien-3-one only occurred when fresh tissue was used, whereas reduction of [5α-3H]5α-androst-16-en-3-one was unaffected by storage of testis at −20°C. 6. NADPH was the preferred cofactor for the reduction of androsta-4,16-dien-3-one. 7. The previously established conversion of androsta-5,16-dien-3β-ol into androsta-4,16-dien-3-one was shown to be reversible, NADH and NADPH being equally effective cofactors. 8. Pathways of biosynthesis of 5α-androst-16-en-3α- and 3β-ols, with the C19 3-oxo steroids as intermediates, are presented.

Fresh tissue parathyroid allotransplantation with short-term immunosuppression: 1-year follow-up

2017 ◽  
Vol 31 (11) ◽  
pp. e13086 ◽  
Author(s):  
Emrah Yucesan ◽  
Beyza Goncu ◽  
Harun Basoglu ◽  
Nur Ozten Kandas ◽  
Yeliz Emine Ersoy ◽  
...  
Keyword(s):  
Short Term ◽  
Fresh Tissue

A lung cancer genomic risk prediction model derived from paraffin-embedded tissue

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 10059-10059
Author(s):  
D. H. Harpole ◽  
M. M. Joshi ◽  
R. P. Petersen ◽  
D. H. Conlon ◽  
K. Tanaka ◽  
...  
Keyword(s):  
Gene Expression ◽  
Lung Cancer ◽  
Prediction Model ◽  
Risk Prediction ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Short Term ◽  
Fresh Tissue ◽  
Kaplan Meier ◽  
Genomic Risk

10059 Background: We previously developed a validated fresh tissue-based genomic risk model in patients with early stage non-small cell lung cancer (NSCLC) using the Affymetrix U133 plus 2.0 Genechip. Limitations of this fresh tissue-based model include the need for immediate processing and limited availability; however, formalin-fixed, paraffin-embedded (FFPE) tissue is readily available and archived on every patient resected in North America. We investigated the ability of gene expression profiles generated on DNA microarrays using RNA isolated from FFPE NSCLC specimens to distinguish short-term and long-term survivors. Methods: Five to ten 5 um sections of FFPE tumor were collected from 61 NSCLC patients consisting of equal numbers of long- (+5-year) and short-term (<2 year cancer death) survivors. Fifty-five samples were microdissected (6 samples contained no tumor tissue) and RNA was extracted using a proprietary procedure of Response Genetics, Inc. For this feasibility study, Actin 300 < 30 cTs was chosen as a threshold for adequate RNA quantity for amplification to the GeneChip. Amplification and labeling of RNA were done using the Affymetrix two cycle amplification kit. The resulting cRNA was successfully hybridized to the U133 plus 2.0 GeneChip in 54/55 samples (98%). Data were analyzed using the SAM statistical software with Kaplan Meier survival analyses. Results: All analyses were performed using unsupervised hierarchical clustering and blinded duplicate samples had nearly identical gene expression profiles, indicating reproducibility. Adenocarcinoma segregated from squamous cell carcinoma with 98% accuracy (p=0.00004). A differentially expressed gene list between long and short survivors was determined. Distinct gene clusters were observed within each histological type segregating the tumors according to outcome. Kaplan Meier survival analysis stratifying on these clusters revealed significant differences in survival (cluster 1 and cluster 2 median survival>75 mos. vs. 30 mos., respectively; p<0.001). Conclusions: We have demonstrated the feasibility of creating a preliminary genomic risk prediction model using FFPE NSCLC tissue. Data will be presented on a larger training set (100+ patients) and a separate validation cohort of 100 patients. [Table: see text]

scholarly journals Spermatogenesis and steroidogenesis in mouse, hamster and monkey testicular tissue after cryopreservation and heterotopic grafting to castrated hosts

Reproduction ◽  
2002 ◽  
pp. 339-346 ◽  
Author(s):  
S Schlatt ◽  
SS Kim ◽  
R Gosden
Keyword(s):  
Adult Mouse ◽  
Germ Line ◽  
Testicular Tissue ◽  
Seminiferous Tubules ◽  
Male Germ Line ◽  
Fresh Tissue ◽  
Intact Control ◽  
Adult Mice ◽  
Mature Spermatozoa ◽  
Testis Tissue

Retrieval, extracorporal storage and autotransplantation of testicular tissue could become an important strategy for preserving male gonadal function. The present study used syngeneic and immunodeficient nude mice as hosts, and immature and adult mice, neonatal and adult photoregressed Djungarian hamsters and neonatal marmosets to identify the potential of testicular tissue grafting to maintain the morphological and functional integrity of the testis. Testicular tissue was grafted s.c. either as fresh tissue or after cryopreservation into adult, orchidectomized hosts. The mice that received rodent testis tissue were autopsied 50 days later, and blood samples were collected. Sixty-five per cent of mouse isografts contained morphologically normal testicular tissue and seminiferous tubules with some degree of spermatogenic recovery. Mature spermatozoa were recovered after enzymatic disaggregation. Although the recovery of spermatogenesis was limited in adult mouse and hamster tissue, complete spermatogenesis was observed in grafts from immature rodents. Testicular tissue from neonatal marmosets developed up to the stage of spermatocytes at day 135 after xenografting. Androgen concentrations were comparable in intact control mice and in mice receiving fresh mouse and hamster grafts, slightly lower in mice receiving cryopreserved grafts and adult photoregressed hamster tissue, and low in castrated control mice and in mice receiving marmoset tissue. These results show that isografts and xenografts of immature and adult testicular tissue become functionally active as a s.c. graft in the mouse and that this approach might be useful in combination with cryopreservation as a tool for storage and activation of the male germ line and androgen replacement therapy in patients.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

1977 ◽  
Vol 35 ◽  
pp. 590-591
Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Critical Point ◽  
Avena Sativa ◽  
Substantial Improvement ◽  
Fresh Tissue ◽  
Cold Stage ◽  
Critical Point Drying ◽  
Almost All ◽  
Cell Collapse ◽  
Conductive Paint ◽  
Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

Ultrastructural Changes of Canine Kidneys During 24-Hour Perfusion on a LI-400 Preservation System

1971 ◽  
Vol 29 ◽  
pp. 316-317
Author(s):  
M. O. Magnusson ◽  
D. G. Osborne ◽  
T. Shimoji ◽  
W. S. Kiser ◽  
W. A. Hawk
Keyword(s):  
Electron Microscopy ◽  
Electrolyte Solution ◽  
Ultrastructural Changes ◽  
Midline Incision ◽  
Short Term ◽  
Pentobarbital Anesthesia ◽  
Pulsatile Perfusion

Short term experimental and clinical preservation of kidneys is presently best accomplished by hypothermic continuous pulsatile perfusion with cryoprecipitated and millipore filtered plasma. This study was undertaken to observe ultrastructural changes occurring during 24-hour preservation using the above mentioned method.A kidney was removed through a midline incision from healthy mongrel dogs under pentobarbital anesthesia. The kidneys were flushed immediately after removal with chilled electrolyte solution and placed on a LI-400 preservation system and perfused at 8-10°C. Serial kidney biopsies were obtained at 0-½-1-2-4-8-16 and 24 hours of preservation. All biopsies were prepared for electron microscopy. At the end of the preservation period the kidneys were autografted.

Polychlorinated biphenyl induced hepatocyte alterations

1987 ◽  
Vol 45 ◽  
pp. 716-717
Author(s):  
D.N. Collins ◽  
J.N. Turner ◽  
K.O. Brosch ◽  
R.F. Seegal
Keyword(s):  
Lipid Droplets ◽  
Wistar Rats ◽  
Homovanillic Acid ◽  
Polychlorinated Biphenyl ◽  
Corn Oil ◽  
Environmental Pollutants ◽  
Short Term ◽  
Pcb Congeners ◽  
Urinary Levels ◽  
The Brain

Polychlorinated biphenyls (PCBs) are a ubiquitous class of environmental pollutants with toxic and hepatocellular effects, including accumulation of fat, proliferated smooth endoplasmic recticulum (SER), and concentric membrane arrays (CMAs) (1-3). The CMAs appear to be a membrane storage and degeneration organelle composed of a large number of concentric membrane layers usually surrounding one or more lipid droplets often with internalized membrane fragments (3). The present study documents liver alteration after a short term single dose exposure to PCBs with high chlorine content, and correlates them with reported animal weights and central nervous system (CNS) measures. In the brain PCB congeners were concentrated in particular regions (4) while catecholamine concentrations were decreased (4-6). Urinary levels of homovanillic acid a dopamine metabolite were evaluated (7).Wistar rats were gavaged with corn oil (6 controls), or with a 1:1 mixture of Aroclor 1254 and 1260 in corn oil at 500 or 1000 mg total PCB/kg (6 at each level).

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