bluuebunny/crossref_metadata_2025 huggingface dataset:
Endothelin‐1 and Its Receptors in Human Testis
Authors: MAGGI M. , BARNI T. , ORLANDO C. , FANTONI G. , FINETTI G. , VANNELLI G. B. , MANCINA R. , GLORIA L. , BONACCORSI L. , YANAGISAWA M. , FORTI G.
Published: October 2023

ABSTRACT: We have previously found the presence of endothelin (ET) receptor and ET‐like immunoreactivity in rat testis. We now extend our studies from rat to human testis. We found expression of a specific transcript for ET‐1 and ET‐1‐like immunoreactivity in human testis. Positive staining was confined to the Sertoli cells of the tubular compartment, although few peritubular and interstitial cells were also stained. We also identified specific ETA and ETB receptor transcripts in human testis; ETA expression was more abundant than the ETB expression. Mathematical analysis of multiple self‐and cross‐competition studies among [125I]ET‐1, [125I]ET‐3, and analogues confirmed the presence of the ETA and ETB isoreceptors. In testicular homogenates, the ETA receptor was sevenfold more concentrated than the ETB receptor. In order to localize the receptors, we performed [125I]ET‐1 autoradiography. Binding sites were mostly concentrated into the seminiferous tubules, although interstitial and peritubular myoid cells were also positive. Within the seminiferous tubules, [125I]ET‐1 binding sites were confined to primary and secondary spermatocytes and early spermatids, whereas Sertoli cells were negative. We were unable to demonstrate the presence of functional ET receptors in ejaculated spermatozoa. Because ET‐like immunoreactivity was present in Sertoli cells, we next asked whether authentic ET‐1 is present in human seminal fluid and represents a good index for Sertoli cell function. Reverse‐phase high‐performance liquid chromatography analysis of ET‐like immunoreactivity in seminal fluid indicated that most of the detected peptides correspond to the ET‐1 precursor, big‐ET‐1. The seminal concentration of ET‐like immunoreactivity was similar in normospermic, oligospermic, azoospermic, and vasectomized men, indicating that ETs are produced in different parts of the male genital tract and that they do not represent an useful tool for the diagnosis of male reproductive diseases. In conclusion, this study demonstrated, for the first time, the presence of ET‐1 and its receptors in human testis.
Hormonal Protection From Cyclophosphamide‐Induced Inactivation of Rat Stem Spermatogonia
Authors: MEISTRICH MARVIN L. , PARCHURI NANDAKISHORE , WILSON GENE , KURDOGLU BELMA , KANGASNIEMI MARKO
Published: October 2023

ABSTRACT: Studies of protection of testicular function from cyclophosphamide with hormonal pretreatment have been limited by the lack of a convenient model for cyclophosphamide‐induced inactivation of stem spermatogonia. In the rat, the mortality from cyclophosphamide had prevented the administration of sufficient dosages to produce detectibie damage to stem spermatogonia. To overcome this problem, we used bone marrow transplantation and sodium 2‐mercaptoethanesulfonate (Mesna) treatment to raise the lethal dose for 50% of the animals (LD50) for cyclophosphamide from 275 to >400 mg/kg body weight. In addition we used irradiation, 2 weeks prior to injection of cyclophosphamide, to greatly enhance the measured toxicity of cyclophosphamide towards stem spermatogonia. Whereas sperm counts at 9 weeks after a 300 mg/kg cyclophosphamide dose were reduced by only a factor of 1.6 without prior irradiation, they were reduced by a factor of 60 when 2.5 Gy of irradiation had been given. Dramatic protection against this toxicity was produced by hormone treatment with a gonadotropin‐releasing hormone (GnRH) antagonist (Nal‐Glu) and an antiandrogen (fluta‐mide) following the radiation but prior to cyclophosphamide. This hormone treatment did not modify the stem cell toxicity of the radiation and it therefore must be protecting stem cells against cyclo‐ phosphamide‐induced damage. Because GnRH antagonist‐antian‐ drogen treatment can protect stem spermatogonial survival and/or function in the rat from cyclophosphamide‐induced damage, if the same principles are applicable in human, hormonal pretreatment should be useful for preventing the prolonged azoospermia caused by chemotherapy with cyclophosphamide‐containing protocols.
Detection of Germ Cell‐Derived Proteins in Testicular Interstitial Fluid: Potential for Monitoring Spermatogenesis In Vivo
Authors: TURNER KATIE J. , McKINNELL CHRIS , McLAREN TANYA T. , QURESHI SAFIA J. , SAUNDERS PHILIPPA T. K. , FOSTER PAUL M. D. , SHARPE RICHARD M.
Published: October 2023

ABSTRACT: The aim of the present study was to assess whether proteins secreted by the seminiferous tubules (ST) can be detected in testicular interstitial fluid (IF) and testicular (TV), spermatic (SV), and peripheral venous (PV) plasma from adult rats. An antiserum was raised against seminiferous tubule‐conditioned medium (STCM) prepared from adult rats and used in conjunction with Western blot analysis to screen IF and blood samples resolved by one‐dimensional (1‐D) and two‐dimensional (2‐D) sodium dodecyl sulfate‐polyacryl‐amide gel electrophoresis (SDS‐PAGE). Samples of IF and PV were analyzed from control adult rats and rats exposed to scrotal heating (43°C for 30 minutes) 24 hours earlier to ascertain whether damage to spermatogenesis would affect ‘leakage’ of proteins from the seminiferous tubules. In all control rats, the STCM antiserum specifically detected three proteins in testicular IF with molecular weights of 24, 16, and 14 kDa, respectively. Heat treatment increased the abundance of these proteins and induced the appearance of several other less‐abundant proteins, all with molecular masses below 25 kDa. Two of the proteins present in IF were identified, the 24‐kDa protein as phosphatidylethanolamine‐binding protein (PEBP), and the 14‐kDa protein as an androgen‐regulated protein (ARP‐2). Both of these proteins have been shown in previous studies to be secreted by round spermatids. Our results suggest that germ cell secretory products can gain access to the interstitium under both normal physiological conditions and more easily after induction of damage to spermatogenesis. The antiserum was unable to detect any ST‐derived proteins in blood, although it is likely that this result may be due to insensitivity of the presently used techniques. The development of specific immunoassays for germ cell‐secreted proteins (e.g., PEBP and ARP‐2) should enable more definitive assessment of whether proteins secreted by the seminiferous epithelium can be measured in blood and thus provide a potential means of monitoring spermatogenesis.
The Development of the Baboon Prostate: Ultrasound Methodology, Modelling, and Natural History
Authors: JIN BO , TURNER LEO , CRAWFORD BRONWYN , BIRRELL ALEX , HANDELSMAN DAVID J.
Published: October 2023

ABSTRACT: In order to evaluate the potential of ultrasound for serial, nontraumatic estimation of prostate size in the hamadryas baboon (Papio hamadryas), we adapted the technique of planimetric ultrasound to study a captive‐bred colony of 30 male baboons (median age 8.4 years, range 3.3–17 years) including 4 long‐term castrates. Most (19) were studied on another two occasions (at 33‐ and 43‐day intervals) to estimate reproducibility of the prostate size (dimensions, volume) measurement. Prostatic dimensions were measured with a B‐mode sector ultrasound using a 7.5‐MHz transrectal transducer by planimetry at 2.5‐mm steps from base to apex as well as the maximum three dimensions of the prostate. The planimetric volume estimate was reproducible (intraclass coefficient 0.81) with coefficient of variation (CV) of 24.3% for all, and t6.0% for mature, baboons. The prostate dimensions were also reproducible (CVs 7.9‐3.4%). Prostate volume estimates based on the general ellipsoidal model were reasonably reproducible (19.9% for all, 12.9% for mature) but were biased in relationship to the planimetric volume (0.57 ± 0.19, P = 0.004). Using the independent estimates of prostate volume and dimensions, we developed an empirical power‐function model of prostate shape based on the generalized ellipsoidal model that was robust and unbiased (‐0.07 ± 0.15, P = 0.64) with respect to the planimetric volume. This model provides a simpler and accurate formula for prostate volume based on its three maximal dimensional measurements. The natural history of prostate growth in the hamadryas baboon was illustrated by sigmoidal correlations with age (ED50, = 6.0 years, plateau ED95 = 8.3 years), body weight (ED50 = 14.6 kg, ED95 = 16.1 kg), and testis volume (ED90 = 7.8 ml, ED95 = 18.4 ml). Between‐animal variability among mature baboons was greater for prostate weight (27%) than body weight (10%), raising the possibility that a subgroup of these baboons may develop spontaneous age‐related prostatic hyperplasia. These findings suggest that ultrasonic evaluation of prostate size in the hamadryas baboon may constitute a suitable model for spontaneous benign prostatic hyperplasia and for experimental studies of prostate growth, development, and hormonal regulation.
Stage‐Specific Apoptosis in the Rat Seminiferous Epithelium: Quantification of Irradiation Effects
Authors: HENRIKSéN KENTH , KULMALA JARMO , TOPPARI JORMA , MEHROTRA KALIKA , PARVINEN MARTTI
Published: October 2023

ABSTRACT: The effects of 3 Gy local X‐irradiation on the adult rat testis were studied together with exact determination of the radiation dose distribution in the testis. Seminiferous tubule segments were isolated 8–66 hours postirradiation (p.i.), squashed between a microscope slide and a coverslip, and the exact stage of the seminiferous epithelial cycle was identified under a phase‐contrast microscope. The squash preparations were subjected to in situ end labeling (ISEL) for visualization and quantification of apoptotic cells. In controls, the highest numbers of apoptotic cells were scored in stages XII‐XIV and I. In situ end‐label staining of cells was observed in A3‐A4 spermatogonia, spermatocytes at zygotene, pachytene, and meiotic division phases, as well as in early spermatids. In irradiated testes, from 8 hours p.i. and onward, intermediate‐ and B‐type spermatogonia were sensitive at stages II‐VI. At 42 hours, in stage I, elevated numbers of degenerating spermatocytes were seen. Most of them had not undergone meiotic divisions at stage XIV and showed an apoptotic type of degeneration at stage I. At the time of irradiation, the cells were in stage XIII, suggesting that diakinetic spermatocytes are particularly sensitive to irradiation. Also, preleptotene‐zygotene spermatocytes in stages VII‐XII were sensitive to irradiation. Apoptotic‐type of cell degeneration was confirmed by living cell squash preparations, electron microscopy, and DNA electrophoresis. In conclusion, irradiation may provide a useful model system for studying apoptosis, and its control in spermatogonia and meiotically dividing cells.
Effects of Substrate and Separation Method on Acrosin Amidase Measurements
Authors: Breden Thomas G. , Berg Richard , Plotka Edward D.
Published: October 2023

ABSTRACT: The purpose of this study was to increase the accuracy and reproducibility of the acrosin amidase assay and to assess the effects of different methods of sperm isolation on total sperm acrosin activity. Specific acrosin activity was measured by the procedure described by Kennedy et al (1989) comparing the usual substrate, N‐α‐benzoyl‐DL‐arginine‐p‐nitroanalide hydrochloride (DL‐BAPNA) with the L‐ (L‐BAPNA) and D‐ (D‐BAPNA) isomers. Activity measurements were also compared on sperm isolated by methods: (1) centrifugation through buffered Ficoll, (2) method 1 plus an additional wash in buffered Ficoll, (3) back addition of supematant from method 1 to spermatozoa isolated by method 2, and (4) swim‐up into synthetic human tubal fluid media (mHTF) and using L‐BAPNA.

The specific activity of acrosin was dependent on substrate concentration up to 2.1 mM DL‐BAPNA and 2 mM L‐BAPNA. The maximum reliable solubility of DL‐BAPNA was approximately 2.1 mM in 10% dimethylsulfoxide (DMSO): 90% detergent buffer. There were no solubility constraints for L‐BAPNA through 6.3 mM (> 5 × Km). D‐BAPNA (1 mM) was not hydrolyzed by acrosin. Mean specific acrosin activity was higher using 6.3 mM L‐BAPNA (159 ± 11.4 μIU/106 sperm) than with 2.1 mM DL‐BAPNA (81.4 ± 10.9 μIU/106 sperm; P < 0.001, n = 16). Sperm isolated by methods 2 and 4 had higher specific acrosin activity than sperm isolated by method 1 (P = 0.002). Sperm treated per method 3 had similar acrosin activity as sperm isolated by method 1 (140 ± 14.1 vs. 149 ± 13.8 μIU/106 sperm). The Km for acrosin, calculated through 6.3 mM L‐BAPNA, was 0.6 μIU/106 sperm. L‐BAPNA is superior to DL‐BAPNA as substrate for a clinical acrosin assay, increasing the reproducibility and accuracy of the assay. Simple Ficoll separation is not completely effective at removing acrosin inhibitors and additional separation steps may be necessary to assess true acrosin activity.
Expression of Apolipoprotein E mRNA in the Epithelium and Interstitium of the Testis and the Epididymis
Authors: LAW G. LYNN , McGUINNESS MICHAEL P. , LINDER CAROL C. , GRISWOLD MICHAEL D.
Published: October 2023

ABSTRACT: Apolipoprotein E (apo E) is an important constituent of plasma lipoproteins and is believed to be involved in the regulation of lipid transport and distribution between tissues. The production of this apolipoprotein in extra‐hepatic tissues such as the testis and epididymis could facilitate specific local functions. Apo E mRNA was detected in testis, epididymis, seminal vesicles, and prostate. In the epididymis, apo E was detected using in situ hybridization in epithelial cells and in some cells in the interstitium throughout the organ (i.e., caput, corpus, and cauda). Northern blot analysis showed that apo E mRNA is present in Sertoli cells and germ cells, but not peritubular myoid cells. Interstitial cells of the testis displayed the most intense signal for apo E message using in situ hybridization. Messenger RNA for apo E was also detected in the interstitium of rat testes at 3 and 6 days after animals were treated with ethylene dimethanesulfonate (EDS) to eliminate Leydig cells. Thus, in addition to Leydig cells, other cell types within the interstitium are capable of producing apo E message. Levels of testicular apo E mRNA increased between 30 and 60 days pc during which the germ cell population is increasing. As determined by northern blot analysis of RNA from stage synchronized testes, the levels of apo E mRNA fluctuate in relation to the cycle of the seminiferous epithelium. The cells responsible for this stage‐specific variation in message could not be identified by in situ hybridization. Apolipoprotein A1 (apo A1) mRNA was also found to be expressed in the epididymis but not in the testis of adult rats. The role of apolipoproteins in spermatogenesis and sperm maturation has not been elucidated. The results of this study demonstrate the specific tissues and cells types which play a role in the production and possible regulation of apo E mRNA in the male reproductive tract. These data will help in the elucidation of the function of apo E in spermatogenesis and sperm maturation.
Characterization and Developmental Expression of a Testis‐Specific Adenosine Deaminase mRNA in the Mouse
Authors: MENG JIAN‐PING , ZHANG FU‐PING , HUHTANIEMI ILPO , PAKARINEN PIRJO
Published: October 2023

ABSTRACT: Adenosine is able to alter intracellular cAMP levels and to affect the physiological functions of sperm. It also modulates FSH action through its Gi protein coupled receptors. Adenosine deaminase (ADA), an enzyme regulating adenosine levels, exists in the plasma membrane of the sperm, but little is known about its action on testicular function. The present study investigates the expression of a testis‐specific ADA mRNA with development and in comparison to several other tissues in the mouse. In addition, the sequence of a testis‐specific ADA cDNA was determined from an adult mouse testis library. We demonstrate for the first time the presence of a major 1,350 bp testis‐specific ADA mRNA and a weaker 1,200 bp ADA transcript whose developmental expression starts on day 28 of life. Sequence analysis of the testis‐specific ADA cDNA indicated that exons 1 and 2, as well as the first 8 nucleotides of exon 3 of the somatic cell ADA cDNA, were absent in the testicular ADA cDNA. The deduced open reading frame of the testis‐specific ADA cDNA indicates absence of the first 51 amino acids at the 5′ end that are present in the somatic cell ADA protein. The developmental onset of expression of the testis‐specific ADA mRNA may be related to specific proliferation/differentiation events of spermatogenesis.
Effects of a 5α‐Reductase Inhibitor, Finasteride, on the Developing Prostate and Testis of a Marsupial
Authors: RYHORCHUK ALEXA R. , SHAW GEOFFREY , BUTLER CHRISTOPHER M. , RENFREE MARILYN B.
Published: October 2023

ABSTRACT: This study examines the role of dihydrotestosterone in virilization of the developing male tammar. The onset of prostate differentiation in this marsupial species normally occurs around 25 days postpartum, long after the onset of testicular testosterone production immediately after birth and the appearance of 5α‐reductase in the urogenital sinus before day 10. Males treated with the 5α‐reductase inhibitor Finasteride had reduced prostatic growth and development, and their testicular structure was disorganized. Exogenous testosterone in males enhanced the development of prostatic buds but also caused damage to the testis structure. Treatment of female tammars with testosterone between days 20–30 postpartum stimulated prostatic tissue formation and Wolffian duct development, confirming that prostatic differentiation is initiated by androgens and occurs over a relatively narrow window of time. Testosterone had a deleterious effect on the ovary, destroying the germ cells. Although treatment with testosterone damaged gonadal cellular structure in both male and female tammar young, dihydrotestosterone is apparently necessary for stability of the seminiferous tubules in the testis. Taken together, these results suggest that dihydrotostesterone initiates prostatic development between days 20 and 25 after birth in this marsupial.
Objectively Measured Boar Sperm Motility Parameters Correlate With the Outcomes of On‐Farm Inseminations: Results of Two Fertility Trials
Authors: HOLT CLARE , HOLT WILLIAM V. , MOORE HARRY D. M. , REED HUGH C. B. , CURNOCK ROBERT M.
Published: October 2023

ABSTRACT: Two fertility trials were undertaken to evaluate the relationship between boar semen quality and fertility (conception rate and litter size) after on‐farm artificial insemination (AI). Trial 1 included 98 ejaculates from 27 boars, and trial 2 included 72 ejaculates from 26 boars. The semen quality was measured by computer‐assisted semen analysis (CASA) using the Hobson Sperm Tracker. Boar semen was diluted in a standard extender (Beltsville Thawing Solution, BTS), dispensed into 75 ml aliquots each containing 1.5 × 10° spermatozoa and dispatched to farms by overnight mail for use by their normal AI procedures. Randomly selected 75 ml aliquots of semen from each boar were also sent to the Institute of Zoology for CASA measurement. Prior to CASA analysis, the spermatozoa were recovered from the BTS using Percoll gradients, resuspended in tris‐buffered saline media containing 40 mM Ca++, and incubated at 39°C. Parameters of sperm motion were measured after 0, 2, 4, and 6 hours of incubation. Various multiple regression models based on measured motion parameters could account for up to 24% of the variation in litter size. Using logistic regression, highly significant (P < 0.0001) models explaining conception rate in terms of sperm motion were derived for trial 2 only. The change in sperm velocity during the first 2 hours of incubation and the magnitude of the velocity parameters after 2 hours were identified as the most consistent indicators of fertility. Other attributes of sperm quality, i.e., frequency of spontaneous acrosome reactions (AR) and ARs induced by ionophore A23187 or solubilized pig zona pellucida, were also examined. When the “within‐trial” median litter size was used as a way of allocating ejaculates to “high” or “low” litter‐size groups, higher litter size was associated with lower frequency of both spontaneous and induced AR. These results demonstrate that fertility information can be derived from the CASA analysis of boar semen provided it is combined with a period of incubation in capacitating conditions.
Pharmacokinetics of 7α‐Methyl‐19‐nortestosterone in Men and Cynomolgus Monkeys
Authors: KUMAR NARENDER , SUVISAARI JANNE , TSONG YUN‐YEN , AGUILLAUME CLAUDE , BARDIN C. WAYNE , LÄHTEENMAKI PEKKA , SUNDARAM KALYAN
Published: October 2023

ABSTRACT: Testosterone and its esters are widely used for androgen replacement therapy. In the prostate, testosterone is 5α‐reduced to dihydrotestosterone (DHT), which leads to an amplification of its stimulatory activity in this and other tissues that have significant 5a‐reductase activity. While this amplification is essential during fetal development, it has potentially undesirable consequences during adult life. 7α‐Methyl‐19‐nortestosterone (MENT) is a potent synthetic androgen that does not undergo 5α reduction and is therefore being investigated for long‐term clinical use because it is expected to be less stimulatory to the prostate. Since we anticipate using MENT acetate (MENT Ac) rather than MENT as the form of this androgen in humans, the bioavailability of MENT following the administration of MENT and MENT Ac was investigated in cynomolgus monkeys. Equimolar concentrations of MENT or MENT Ac were administered as a continuous subcutaneous infusion via Alzet osmotic pumps. Serum MENT levels were measured by radioimmunoassay (RIA) in blood samples collected daily for 4 days during steady state. The serum MENT levels were not significantly different in the two groups (11.3 ± 1.6 vs. 13.1 ± 1.2 nmol/L). This suggested that MENT Ac was rapidly converted to MENT in circulation. The hydrolysis of MENT Ac to MENT was confirmed by the in vitro incubation of MENT Ac with blood or plasma and the demonstration of MENT in products following separation by high‐performance liquid chromatography (HPLC). Following the demonstration of the safety of MENT Ac in subchronic toxicity studies in rats and rabbits, a pharmacokinetic study was performed in men. In normal men, a single intravenous bolus of 500 μg of MENT led to peak serum MENT levels at 3 minutes after dosing (when the first samples were collected), followed by an exponential decline, reaching undetectable levels by 180 minutes. The average terminal half‐life and the metabolic clearance rate (MCR) were calculated to be 40 minutes and 2,360 L/day, respectively. The results of the pharmacokinetic studies show that in both men and monkeys, the MCR of MENT is much faster than the values reported for testosterone. The faster MCR can be attributed, in part, to the finding that, in contrast to testosterone, MENT showed no binding to sex hormone binding globulin (SHBG).
Relationship Between Sleep‐Related Erections and Testosterone Levels in Men
Authors: GRANATA ANTONIO R. M. , ROCHIRA VINCENZO , LERCHL ALEXANDER , MARRAMA PAOLO , CARANI CESARE
Published: October 2023

ABSTRACT: In order to identify a possible threshold for a serum testosterone level below which sleep‐related erections are impaired and to compare this threshold with the normal laboratory range of testosterone serum levels, we studied 201 men, including hypogonadal and eugonadal subjects. The protocol included nocturnal penile tumescence and rigidity monitoring and the assay of basal testosterone, prolactin, luteinizing hormone (LH), and follicle‐stimulating hormone (FSH) serum levels. The subjects were assigned to eight groups according to their testosterone serum levels. Group 1 had testosterone between 0 ng/dl and 99 ng/dl; the following seven groups had testosterone levels increased by 100 ng/dl per group. The groups of subjects with higher testosterone serum levels showed almost constantly higher values for the erectile parameters we studied than the subjects with serum testosterone ≤99 ng/dl. On the contrary, subjects with higher testosterone serum levels showed higher values for only some erectile parameters compared to the subjects with serum testosterone between 100 and 199 ng/dl, without any significant difference among the groups with testosterone serum levels in the normal range. Our data suggest that the serum testosterone threshold for sleep‐related erections is lower than the low end of the normal laboratory male range and is about 200 ng/dl. Further efforts are needed to find the precise serum testosterone ranges related to normal sleep‐related erections and to normal sexual behavior, the testosterone ranges of which will probably not coincide.
Chromatin Structural Changes in Sperm After Scrotal Insulation of Holstein Bulls
Authors: KARABINUS DAVID S. , VOGLER CHERYL J. , SAACKE RICHARD G. , EVENSON DONALD P.
Published: October 2023

ABSTRACT: The reported effects on semen quality ascribed to testicular heat stress generally relate to traits impacting sperm transport and fertilizing ability but not to the genetic material contained by the sperm. To characterize the effects of testicular heat stress on sperm chromatin, susceptibility of DNA in sperm nuclear chromatin to in situ acid denaturation was measured by flow cytometry after staining with acridine orange using the sperm chromatin structure assay (SCSA). Semen was collected from Holstein bulls at 3‐day intervals, before and after 48‐hour scrotal insulation, until the morphologically abnormal sperm content in raw semen exceeded 50%. After cryo‐preservation in egg yolk—citrate extender, semen was thawed and sampled during incubation in vitro at 38.5°C. Overall, SCSA results showed that chromatin susceptibility to denaturation was increased for sperm collected post‐ vs. preinsulation and was more pronounced for sperm presumably in the testes during insulation than for those sperm presumably in the epididymides. Increased susceptibility was detected as early as the first collection postinsulation; however, chromatin of sperm presumably in the proximal epididymis during insulation did not appear to have been detrimentally affected. Chromatin susceptibility to denaturation increased with increased incubation time in vitro, but the rate of change in susceptibility during incubation did not differ among pre‐ vs. postinsulation specimens. We conclude that elevated scrotal temperatures adversely affect both epididymal and testicular sperm by reducing sperm chromatin stability. The effects of heat stress on the chromatin of epididymal sperm were more subtle than those exhibited by testicular sperm but detectable within close proximity to the heat stress event.
The Human Acrosome Reaction Is Highly Sensitive to Inhibition by Cyclodiene Insecticides
Authors: TURNER KENNETH O. , SYVANEN MICHAEL , MEIZEL STANLEY
Published: October 2023

ABSTRACT: The mammalian sperm acrosome reaction (AR) is essential to fertilization. It can be initiated in vitro by progesterone, a putative physiological initiator that helps to activate sperm GABAA receptor/chloride channels and by glycine, a substitute for the egg zona pellucida, which activates sperm glycine receptor/chloride channels. Even at 1 nM (0.41 ng/ml or 0.41 ppb), chlordane and endosulfan, chlorinated cyclodiene blockers of insect neuronal GA‐BAA receptor/chloride channels, strongly inhibited the AR initiated by progesterone or glycine. Inhibition of the latter was also seen at 0.1 nM chlordane and endosulfan, but neither cyclodiene inhibited either AR initiator at 0.01 nM. Inhibitory concentrations of these cyclodienes are well within the range detected in human and wildlife tissue and fluids as a result of environmental contamination.
Androgenic Maintenance of the Rat Erectile Response Via a Non‐Nitric‐Oxide‐Dependent Pathway
Authors: REILLY CHRISTOPHER M. , LEWIS RONALD W. , STOPPER VIVIESNNE S. , MILLS THOMAS M.
Published: October 2023

ABSTRACT: Prior studies have demonstrated that the erectile response in the rat penis is androgen dependent and is mediated by nitric oxide (NO), the neurotransmitter synthesized by the enzyme nitric oxide synthase (NOS). The present studies used l‐nitro‐l‐arginine methyl ester (L‐NAME), an inhibitor of NOS, to determine if androgens also regulate alternative pathways leading to the erectile response but not mediated by NO. Castrated rats that were treated with L‐NAME (L‐NAME CASTRATE) exhibited little or no increase in intracavemosal pressure in response to stimulation of the major pelvic ganglion. This ganglion controls blood flow into the penis and, when stimulated, normally leads to erection. However, when castrated animals were treated with testosterone along with L‐NAME (L‐NAME TESTO), the animals responded to the ganglionic stimulation with increased intracavemosal pressure. This finding suggests that there are other androgen‐dependent pathways that lead to penile erection but are not mediated by NO. Erection occurred in both L‐NAME CASTRATE and L‐NAME TESTO rats in response to intracavemosal injection of sodium nitroprusside (an NO donor drug), proving that the NO responsive mechanisms were unaffected by the inhibition of NOS activity. To investigate further the nature of this NO independent pathway, L‐NAME CASTRATE and L‐NAME TESTO rats were treated with either zaprinast (a specific phosphodiesterase 5 inhibitor), which would block the breakdown of cGMP to 5′GMP, or methylene blue (an inhibitor of guanylate cyclase) to prevent the synthesis of cGMP. Zaprinast treatment led to increased erectile response in L‐NAME TESTO rats but not in L‐NAME CASTRATE rats, demonstrating that androgen‐sensitive alternative pathways increased guanylate cyclase activity. Methylene blue inhibited the erectile response in all treatment groups, showing that cyclic GMP is critical to the NO‐independent pathway as well as the NO‐dependent pathway. Taken together, these results support the hypothesis that androgens maintain the erectile response by alternate pathways, including one that is independent of NO but involves the synthesis of cyclic GMP.
Effect of Repeated Testicular Biopsy on Testis Function and Semen Quality in Dogs
Authors: HUNT W. LYNN , FOOTE ROBERT H.
Published: October 2023

ABSTRACT: The study was designed to quantitatively evaluate the effect of repeated testicular biopsy of avascular areas by the open method on spermatogenesis, semen quality, and sperm output in dogs. After a 5‐week standardization period of semen collections 3x per week, 10 sexually mature Beagle dogs were divided into two groups, approximately equalized based on previous sperm output. Semen collections were continued for 20 weeks. One group was controls without treatment until unilaterally orchidectomized after weeks 16 and 20; a second group had one testis biopsied on weeks 1, 5, and 9 and removed after week 16, with the second testis removed after week 20. Sperm output per week during the summer declined in the control group from 851 × 106 to 725 × 106 (15%). The decline in the biopsied control group collected simultaneously was 22%, presumably reflecting a seasonal effect plus a possible small treatment effect. At 16 weeks, the testes removed from the controls averaged 7.1 g and the testes biopsied three times in the second group averaged 6.4 g (P > 0.05). Scrotal—testicular measurements taken in live animals were correlated with testicular weights at orchidectomy (r = 0.81). An average of 36.7 mg of tissue was removed at each biopsy, sufficient to evaluate 100 to >200 seminiferous tubules in cross‐section. Sperm motility and frequency of all stages of the cycle of the seminiferous epithelium were similar between control and biopsied dogs. It is concluded that repeated testicular biopsy of avascular areas can provide sufficient tissue for histopathologic evaluation without significant interference with spermatogenesis.
Forecasting and stress testing with quantile vector autoregression
Authors: Chavleishvili Sulkhan , Manganelli Simone
Published: October 2023

A quantile vector autoregressive (VAR) model, unlike standard VAR, traces the interaction among the endogenous random variables at any quantile. Quantile forecasts are obtained by factorizing the joint distribution in a recursive structure but cannot be obtained from reduced form estimation. Identification strategies and structural quantile impulse response functions are derived as generalization of the VAR model. The model is estimated using real and financial variables for the euro area. The dynamic properties of the system change across quantiles. This is relevant for stress testing exercises, whose goal is to forecast the tail behavior of the economy when hit by large financial and real shocks.
Cover crop performance under a changing climate in continuous corn system over Nebraska
Authors: Birru Girma , Shiferaw Andualem , Tadesse Tsegaye , Wardlow Brian , Jin Virginia L. , Schmer Marty R. , Awada Tala , Kharel Tulsi , Iqbal Javad
Published: October 2023

Fall‐planted cover crop (CC) within a continuous corn (Zea mays L.) system offers potential agroecosystem benefits, including mitigating the impacts of increased temperature and variability in precipitation patterns. A long‐term simulation using the Decision Support System for Agrotechnology Transfer model was made to assess the effects of cereal rye (Secale cereale L.) on no‐till continuous corn yield and soil properties under historical (1991–2020) and projected climate (2041–2070) in eastern Nebraska. Local weather data during the historical period were used, while climate change projections were based on the Canadian Earth System Model 2 dynamically downscaled using the Canadian Centre for Climate Modelling and Analysis Regional Climate Model 4 under two representative concentration pathways (RCP), namely, RCP4.5 and RCP8.5. Simulations results indicated that CC impacts on corn yield were nonsignificant under historical and climate change conditions. Climate change created favorable conditions for CC growth, resulting in an increase in biomass. CC reduced N leaching under climate change scenarios compared to an average reduction of 60% (7 kg ha−1) during the historical period. CC resulted in a 6% (27 mm) reduction in total water in soil profile (140 cm) and 22% (27 mm) reduction in plant available water compared to no cover crop during historical period. CC reduced cumulative seasonal surface runoff/soil evaporation and increased the rate of soil organic carbon buildup. This research provides valuable information on how changes in climate can impact the performance of cereal rye CC in continuous corn production and should be scaled to wider locations and CC species.
Exploring the versatility of carbohydrates in surimi and surimi products: novel applications and future perspectives
Authors: Sijin Zhang , Zhang Liangzi , Yin Tao , You Juan , Liu Ru , Wang Lan , Huang Qilin , Wang Weisheng , Ma Huawei
Published: October 2023

Carbohydrate is one kind of the most important additives in the production of surimi and surimi products, mainly due to its wide range of sources and superior functionality. In recent years, new carbohydrates (oligosaccharides and polysaccharides) have been gradually applied in the production of surimi and surimi products which is mainly driven by consumer requirement on nutritional and the flavors or taste quality and producer requirement on extending the shelf life, like low calorie intake, dietary fiber enrichment, rich taste and improvement of antioxidant properties. Besides anti‐freezing and improvement in gelling ability, novel functionalities have been explored such as fat substitution, improving flavor, antibacterial effect, antioxidant effect and improving three‐dimensional printability. With an in‐depth study of the mechanism of carbohydrate improving the qualities of surimi and surimi products, the application of carbohydrates in surimi would be more effective. Therefore, this review summarizes the new carbohydrates applied in the processing of surimi and surimi products, and their novel functionalities. Additionally, progress of the research on the mechanism of carbohydrate improving the qualities of surimi is also reviewed. © 2023 Society of Chemical Industry.
Multi‐objective optimal power flow using grasshopper optimization algorithm
Authors: Mandal Barun , Roy Provas Kumar
Published: October 2023

This paper introduces grasshopper optimization algorithm to efficiently prove its superiority in the optimal power flow problem. To demonstrate the efficiency of the proposed algorithm, it is implemented on the standard IEEE 30‐bus, IEEE 57‐bus, and IEEE 118‐bus test systems with different objectives that reveal presentation indices of the power system. Twelve different cases, in single and multi‐objective optimization space, are considered on different curves of fuel cost, environmental pollution emission, voltage profile, and active power loss. The simulation results obtained from grasshopper optimization algorithm techniques are compared to other new evolutionary optimization methods surfaced in the current state‐of‐the‐art literature. It is revealed that the proposed approach secures better consequence over the other newly originated popular optimization techniques and reflects its improved quality solutions and faster convergence speed. The results obtained in this work demonstrate that the grasshopper optimization algorithm method can successfully be applied to solve the non‐linear problems connected to power systems.
Chemical profiling of botanical extracts obtained in NADES systems using centrifugal partition chromatography combined with 13C NMR dereplication—Hypericum perforatum as a case study
Authors: Kotland Alexis , Thiery Joseph , Hubert Jane
Published: October 2023

Introduction

Natural deep eutectic solvents (NADES) have emerged as interesting extractants to develop botanical ingredients. They are nontoxic and biodegradable, nonflammable, easy to prepare, and able to solubilize a wide range of molecules. However, NADES extracts remain difficult to analyze because the metabolites of interest stay highly diluted in the nonvolatile viscous NADES matrix.

Objective

This study presents a robust analytical workflow for the chemical profiling of NADES extracts. It is applied to Hypericum perforatum aerial parts extracted with the neutral mixture fructose/glycerol/water (3/1/1, w/w/w), and compared to the chemical profiling of a classical dry methanol extract.

Methods

Exploiting polarity differences between metabolites, the H. perforatum NADES extract was partitioned in a liquid–liquid solvent system to trap the hydrophilic NADES constituents in the lower phase. The upper phase, containing a diversity of secondary metabolites from H. perforatum, was fractionated by centrifugal partition chromatography. All fractions were chemically investigated using a 13C NMR dereplication method which involves hierarchical clustering analysis of the whole NMR dataset, a natural metabolite database for metabolite identification, and 2D NMR analyses for validation. Liquid chromatography–mass spectrometry (LC‐MS) analyses were also performed to complete the identification process.

Results

A range of 21 metabolites were unambiguously identified, including glycosylated flavonols, lactones, catechins, phenolic acids, lipids, and simple sugars, and 15 additional minor extract constituents were annotated by LC‐MS based on exact mass measurements.

Conclusion

The proposed identification process is rapid and nondestructive and provides good prospects to deeply characterize botanical extracts obtained in nonvolatile and viscous NADES systems.
Student perceptions of scientific writing in pharmacology: Student generation of collaborative rubrics to score a social pharmacology writing project
Authors: Enslein Terri , Kosack Edward , Wetzel Hanna N.
Published: October 2023

Scholarly writing is an important skill in all fields of study. Despite a strong focus on writing in many courses, faculty and students have disparate expectations related to scholarly writing. Herein, a classroom exercise is presented in which students were asked to develop a rubric that would be used to evaluate their summative writing assessment. Students were provided with a list of elements that commonly represent good scholarly writing, asked to define what effectively demonstrating these elements looks like, and asked to assign the weight that would be given to each element. The weights given to each element by students were compared to a faculty‐generated, departmental writing rubric. Students assigned significantly higher weights to ideas, and significantly lower weights to sentence fluency. Overall, students favored content over writing mechanics. A random selection of student papers was scored using both the departmental rubric and the student rubric, with about a half‐letter grade difference between the two groups, though the difference was not statistically significant. The outcomes suggest this exercise may be valuable in offering insight into student perceptions of scholarly writing and in furthering student engagement in the writing process.
Bacterial endophytes inhabiting desert plants provide protection against seed rot caused by Fusarium verticillioides and promote growth in maize
Authors: Dinango Vanessa Nya , Dhouib Hanen , Wakam Louise Nana , Kouokap Lanvin Kepngop , Youmbi Diane Yimta , Eke Pierre , Driss Fatma , Tounsi Slim , Boyom Fabrice Fekam , Frikha‐Gargouri Olfa
Published: October 2023

BACKGROUND

Fusarium maize ear and root rot disease caused by Fusarium verticillioides has become one of the most serious fungal diseases associated with maize production. Due to their abilities to promote plant development and manage diseases, bacterial endophytes provide a more promising approach for treating this vascular disease.

RESULTS

This work was undertaken for the selection and identification of promising isolates as plant growth promoters and biocontrol agents against F. verticillioides in maize agroecosystems. A screening procedure consisting of in vitro and in situ tests was applied to 27 endophytic strains originating from desert plants: Euphorbia antiquorum, Calotropis procera, and Alcasia albida. In vitro studies indicated that the bacteria exhibited variable results in biocontrol, endophytism, and plant growth‐promoting traits. In addition, in situ plant growth promotion and biocontrol experiments allowed the identification of the most promising bacterial endophytes. In vitro and in situ comparative study results indicated a low correlation. Our data revealed that in situ screening must be used as the method of selection of biocontrol agents against Fusarium ear and root rot disease. Based on in situ results, seven potent strains were selected and identified as Bacillus subtilis, Bacillus velezensis, Bacillus tequilensis, Stenotrophomonas maltophilia, and Klebsiella pneumoniae.

CONCLUSION

The results of this study showed that the selected strains seem to be promising candidates to be exploited as biofertilizers and biocontrol agents against Fusarium maize ear and root rot disease. © 2023 Society of Chemical Industry.
Cross‐resistance, inheritance and biochemical mechanism of abamectin resistance in a field‐derived strain of the citrus red mite, Panonychus citri (Acari: Tetranychidae)
Authors: Liu Xun‐Yan , Li Ke , Pan Deng , Dou Wei , Yuan Guo‐Rui , Wang Jin‐Jun
Published: October 2023

BACKGROUND

The citrus red mite, Panonychus citri (McGregor), a global pest of citrus, has developed different levels of resistance to various acaricides in the field. Abamectin is one of the most important insecticides/acaricides worldwide, targetting a wide number of insect and mite pests. The evolution of abamectin resistance in P. citri is threatening the sustainable use of abamectin for mite control.

RESULTS

The abamectin resistant strain (NN‐Aba), derived from a field strain NN by consistent selection with abamectin, showed 4279‐fold resistance to abamectin compared to a relatively susceptible strain (SS) of P. citri. Cross‐resistance of NN‐Aba was observed between abamectin and emamectin benzoate, pyridaben, fenpropathrin and cyflumetofen. Inheritance analyses indicated that abamectin resistance in the NN‐Aba strain was autosomal, incompletely recessive and polygenic. The synergy experiment showed that abamectin toxicity was synergized by piperonyl butoxide (PBO), diethyl maleate (DEM) and tributyl phosphorotrithiotate (TPP) in the NN‐Aba strain, and synergy ratios were 2.72‐, 2.48‐ and 2.13‐fold, respectively. The glutathione‐S‐transferases activity in the NN‐Aba strain were significantly increased by 2.08‐fold compared with the SS strain.

CONCLUSION

The abamectin resistance was autosomal, incompletely recessive and polygenic in P. citri. The NN‐Aba strain showed cross‐resistance to various acaricides with different modes of action. Metabolic detoxification mechanism participated in abamectin resistance in NN‐Aba strain. These findings provide useful information for resistance management of P. citri in the field. © 2023 Society of Chemical Industry.
Evaluation of 16S rRNA gene primer pairs for bacterial community profiling in an across soil and ryegrass plant study
Authors: Shi Shengjing , Kumar Sandeep , Young Sandra , Maclean Paul , Jauregui Ruy
Published: October 2023

Introduction

As microbes play important roles in many hosts and niches, linking microbiota across niches is becoming an important area of research. Studying microbiota across multiple niches would allow understanding of ecosystem‐level interactions and potential points of better manipulation for agriculture gains. However, a suitable methodology to characterize microbiota from vast different niches is currently lacking. We used the plant shoot and soil as two important niches for this case study.

Materials and Methods

Considering the important linkage plant play in connecting above‐ and below‐ground ecosystems and challenges of working with plant microbiota, we first compared three commonly used 16S ribosomal RNA gene primer pairs targeting V3–V4 or V5–V7 regions coupled with Illumina sequencing for bacterial communities associated with ryegrass shoot. Then the selected primer was used to amplify bacterial communities in soil and rhizosphere samples for comparison with the commonly used 338F/806R. Finally, core operational taxonomic units (OTUs) across soil and plant niches were identified.

Results

Primer pair 799F/1193R amplified the lowest number of plant organelle sequences (<0.2% of total sequences) and consistently showed the highest α‐diversity compared with 338F/806R and 335F/769R. For soil and rhizosphere samples, 799F/1193R also demonstrated significantly higher α‐diversity indices compared with 338F/806R. The bacterial phyla commonly detected by both primer pairs comprised >97% of the total relative abundance in soil and rhizosphere samples. In addition, the differences in bacterial communities of the soil and rhizosphere samples were more evident when using 799F/1193R than 338F/806R. Using the 799F/1193R data set, 50 core bacterial OTUs were identified across soil, rhizosphere and shoot niches, whereas only 38 core OTUs were identified when using 338F/806R. Most of these core OTUs were dominant in either shoot or soil niche.

Conclusion

Primer pair 799F/1193R is suitable for bacterial community studies targeting ryegrass plant and soil microbiota, in particular for cross‐niches studies.