bluuebunny/crossref_metadata_2025 huggingface dataset:
Mouse Epididymal Sperm Contain Active P450 Aromatase Which Decreases as Sperm Traverse the Epididymis
Authors: JANULIS LYNN , HESS REX A. , BUNICK DAVID , NITTA HIROAKI , JANSSEN SARAH , ASAWA YOSHIO , BAHR JANICE M.
Published: October 2023

ABSTRACT: Recently we reported that mouse germ cells in the testis contain active P450 aromatase (P450arom), the enzyme that converts androgens to estrogens. This finding suggested that germ cells have the ability to produce estrogen. Further studies have shown that germ cells in the testis of several species contain P450arom. The goal of this study was to determine if epididymal sperm contain P450arom and if P450arom activity in sperm changes during traversion of the epididymis in the adult mouse. P450arom was localized in sperm present in the efferent ductules and epididymis by immunocytochemistry using an antiserum generated against purified human placental cytochrome P450arom. P450arom immunostaining in sperm was most prominent in sperm located in the proximal caput epididymis, decreased as sperm traversed the corpus epididymis, and was only slightly apparent in sperm in the cauda epididymis. The immunolocalization of P450arom in epididymal sperm was supported by the measurement of P450arom activity in sperm by the 3H2O assay. We found that P450arom activity in sperm significantly decreases as sperm traverse the epididymis. Based upon these observations, we conclude that sperm can synthesize estrogen and that the synthesis of estrogen by sperm present in the efferent ductules and caput epididymis could be important in the process of sperm maturation.
Testosterone Autoregulation of Its Biosynthesis in the Rat Testis: Inhibition of 17α‐Hydroxylase Activity
Authors: DARNEY KIRWIN J. , ZIRKIN BARRY R. , EWING LARRY L.
Published: October 2023

ABSTRACT: Using the in vitro perfused rat testis, the effects of testosterone (T) on its own biosynthesis, and in particular on the inhibition of specific steroidogenic step(s) in the biosynthetic pathway from cholesterol to T, were examined. Rat testes perfused in vitro for 1 hour with medium containing 1.5 μM T secreted significantly less T than control testes in response to physiologic or maximal luteinizing hormone (LH) stimulation. To locate the site(s) of this rapid inhibition, the effects of arterial T infusion on steroidogenesis by testes also infused with pregnenolone (PREG), progesterone (PROG), 17α‐hydroxyprogesterone (17‐PROG), or androstenedione (ADIONE) were measured by summing all the possible reaction products from each substrate. This approach allowed us to examine the effect of T in situ on the reactions: LH‐stimulated PREG secretion; PREG to PROG; PROG to 17‐PROG; 17‐PROG to ADIONE; and ADIONE to T. Only PROG to 17‐PROG (17α‐hydroxylase activity) was inhibited by arterial T infusion. A kinetic examination of the PROG to 17‐ PROG reaction demonstrated that the specific inhibition by T was competitive. The apparent Km for PROG in this system was 16.0 μM, whereas the apparent kl of T was 1.6 μM, indicating a relatively high degree of sensitivity of the reaction to T. Taken together, these data confirm that T is able to regulate its own synthesis and indicate that this autoregulation is the result of rapid, specific inhibition by T of 17α‐hydroxytase activity.
Influence of Semen Collection Method on Ejaculate Characteristics in the Common Marmoset, Callithrix jacchus
Authors: Morrell Jane M. , Küderling Irmgard , Hodges J. Keith
Published: October 2023

ABSTRACT: A source of normal spermatozoa (sperm) is required for many andrological and reproductive studies. Ideally the method used for semen collection should be repeatable and reliable but should not influence sperm characteristics or sperm function. Two methods of semen collection from marmosets, vaginal washing after copulation and electroejaculation, were compared in terms of the success rate in obtaining samples and the characteristics of the sperm suspensions. Vaginal washing was shown to be a reliable, repeatable, and apparently non‐stressful method of obtaining ejaculates, with 8 out of 10 males ejaculating on at least four of the five attempts. The semen was of good quality as assessed by conventional means, and the sperm were highly fertile when used for artificial insemination (Al; 100% conception rate). In contrast, fewer ejaculates were obtained from the same males by electroejaculation (success rate 30%), sperm survival in vitro was reduced compared to sperm collected by vaginal washing (0.93 ± 0.15 days for electroejaculated sperm compared to 1.98 ± 0.3 days for sperm from vaginal washing), and the number of animals giving birth after Al was smaller (0 vs. 6; P < 0.05). The proportions of motile (74.8 vs. 70.7%), live (84.7 vs. 81%), and morphologically normal (91.9 vs. 87.6%) sperm in the ejaculates were not affected by the semen collection method, but velocity parameters, such as curvilinear velocity, straight line velocity, and average path velocity, as assessed by computerized motility analysis, were significantly lower in vaginal washings than in electroejaculates (P < 0.023,0.008, and 0.008, respectively). Mean angular deviation and beat cross frequency were greater in vaginal washings than in electroejaculates (P < 0.016 and 0.008, respectively). Therefore the effect of semen collection method on sperm function should always be considered when designing reproductive studies.
The Effects of Recombinant FSH on Testosterone‐Induced Spermatogenesis in Gonadotrophin‐Deficient (hpg) Mice
Authors: SINGH JASKIRAT , HANDELSMAN DAVID J.
Published: October 2023

ABSTRACT: In order to clarify the mechanism of synergism between follicle‐stimulatory hormone(FSH) and testosterone (T) in the hormonal regulation of spermatogenesis, we studied the effects of recombinant human FSH (rhFSH) on the induction of spermatogenesis by testosterone in congenitally gonadotropin‐deficient hpg mice Weanling (day 21) homozygous hpg mice were administered daily subcutaneous injections of 1, 5, or 10 1U of rhFSH alone or in combination with a subdermal testosterone implant until day 70 of age. Spermatogenesis was quantitated by stereological estimation of germ cell populations and Sertoli cells as well as measurement of diameter of seminiferous tubules and their lumina in perfusion‐fixed testes and by counting homogenization‐resistant condensed testicular spermatids. Recombinant human FSH alone increased the absolute numbers of spermatogonia (x3.5‐fold) and spermatocytes (x3‐fold) compared with untreated hpg mice but did not significantly increase Sertoli cell numbers or form any condensed spermatids or tubular lumen. Relative to Sertoli cell numbers, rhFSH alone increased populations of spermatogonia (x2‐fold) and spermatocytes (x2‐fold). The addition of T to rhFSH further increased the absolute numbers of spermatogonia (x5‐fold) and spermatocytes (x3.5‐fold) compared with untreated hpg mice as well as increasing tubular diameter and forming tubular lumina. In addition administration of T allowed the completion of spermatogenesis in the presence of intra‐testicular T levels that were ≅2% of non‐hpg controls. All effects of the FSH + T combination were however no greater than the effects of the equivalent dose of T atone. The present study therefore indicates that rhFSH alone increases proliferation of premeiotic spermatogenic cells but has no effect on the completion of spermiogen‐ esis or on Sertoli cell maturation. Furthermore we were unable to identify any additive effects of FSH with T in the hormonal regulation of spermatogenesis in the hpg mouse. This suggests that FSH or T both may stimulate initial spermatogenic development, but only T can complete spermiogenesis.
Compromised Sperm Protein Phosphorylation After Capacitation, Swim‐up, and Zona Pellucida Exposure in Teratospermic Domestic Cats
Authors: PUKAZHENTHI BUDHAN S. , WILDT DAVID E. , OTTINGER MARY A. , HOWARD JOGAYLE
Published: October 2023

ABSTRACT: Tyrosine phosphorylated proteins recently have been found in mouse and human spermatozoa. Our objectives were to (1) determine if domestic cat spermatozoa also express tyrosine phosphorylated proteins, and (2) examine the changes in protein phosphorylation between normospermic and teratospermic domestic cats following sperm capacitation, swim‐up separation and exposure to zona pellucida (ZP). Membranes from cat spermatozoa contained two phosphorylated proteins of molecular weights 160 kDa and 95 kDa (designated as p160 and p95) that immunoreacted with monoclonal antibodies to tyrosine phosphate. The p95 protein was distinct from sperm‐specific hexokinase. Following capacitation, the extent of phosphorylation of p95 was increased (P < 0.05) 3‐fold in normospermic cats compared to only 1.75‐fold in teratospermic cats. Similarly, phosphorylation of p160 also increased (P < 0.05) 2.4‐ fold in normospermic compared to 1.84‐fold in teratospermic cats. Although swim‐up separation increased the percentage of normal spermatozoa in teratospermic ejaculates, phosphorylation of p95 in swim‐up aliquots was increased (P < 0.05) only 1.95‐fold in teratospermic cats compared to 2.9‐fold in normospermic counterparts. Likewise, phosphorylation of p160 was lower (P < 0.05) in teratospermic (1.5‐fold) compared to normospermic cats (2.0‐fold) cats. Phosphorylation also was influenced by exposure to cat ZP proteins (P < 0.05). Solubilized cat ZP bound to the sperm proteins of apparent molecular mass 120, 95, 50, 42, 30, 27, 23 and 20 kDa, suggesting a direct binding interaction between p95 and the ZP. Overall, these findings (1) indicate the presence of tyrosine phosphorylated proteins in the domestic cat spermatozoon that directly interact with homologous ZP glycoproteins; (2) demonstrate that cat sperm hexokinase is not phosphorylated on tyrosine residues; and (3) suggest that the diminished phosphorylation efficiency of sperm from teratospermic cats may result in a compromise in capacitation and the acrosome reaction.
Oxidative Stress and Male Infertility
Authors: Sanocka Dorota , Miesel Ralf , Jedrzejczak Piotr , Kurpisz Maciej K.
Published: October 2023

ABSTRACT: We have studied the activity of substances (superoxide dismutase [SOD], catalase [Cat], malonaldehyde, xanthine oxidase [XO], nitric oxide [NOx]) participating in oxidative stress. Seminal plasma samples of 147 ejaculates obtained from normal and from infertile males were examined. Activities of SOD, Cat, and XO were measured chemiluminometrically while malonaldehydes and NOx were measured by spectrophotometer in seminal plasma samples. Ejaculates were previously characterized according to World Health Organization andrological criteria (sperm number, motility, and morphology). Procedures were performed in a university laboratory. Statistically significant changes (in comparison to normozoospermic samples) were noted in activities of SOD, XO, and malonaldehyde levels. The SOD activity exceeded values obtained for normozoospermic samples only in oligozoospermia. Otherwise low SOD levels in analyzed infertile subgroups inversely related to elevated malonaldehydes. Because diminished activity of SOD in seminal plasma was associated with increased levels of malonaldehydes and XO, we could postulate some significance of these monitored substances in evaluation of the cause of male infertility.
P450 Aromatase Messenger Ribonucleic Acid Expression in Male Rat Germ Cells: Detection by Reverse Transcription‐Polymerase Chain Reaction Amplification
Authors: JANULIS LYNN , BAHR JANICE M. , HESS REX A. , BUNICK DAVID
Published: October 2023

ABSTRACT: We have previously demonstrated that cytochrome P450 aromatase (P450arom) protein, an estrogen‐synthesizing enzyme, is present and active in germ cells of the adult mouse testis. To establish that P450arom mRNA is expressed in germ cells of other species, we examined expression of P450arom in adult rat germ cells by employing reverse transcription‐polymerase chain reaction (RT‐PCR). Total RNA was extracted from Sta‐put separated germ cells and reverse transcribed. The resulting cDNA was amplified by nested PCR reactions using oligonucleotide primers selected from a highly conserved region of the P450arom gene. RT‐PCR analysis yielded cDNA products of 334 bp in length that corresponded to the predicted size expected from the final nested amplification. The identity of the germ cell P450arom PCR products was confirmed by restriction enzyme analysis and direct nucleotide sequencing. Rat genomic DNA was subjected to PCR to verify that P450arom DNA products were not obtained from genomic DNA contamination. Rat genomic DNA yielded a nested PCR product for P450arom of approximately 2000 bp, suggesting that, as is the case with the human P450arom gene, the rat P450arom gene contains an intron in the amplified region. In addition, a semiquantitative technique was utilized to eliminate the possibility that the P450arom RT‐PCR products were derived from Leydig cell contamination of Sta‐put‐separated germ cell preparations. RT‐PCR for P450arom and 3‐β‐hydroxysteroid dehydrogenase (3β‐HSD), a Leydig cell‐specific steroidogenic enzyme, was carried out on Sta‐put‐separated germ cells and interstitial cell preparations containing Leydig cells. P450arom and 3β‐HSD RT‐PCR reactions were stopped at three cycle intervals to detect and compare the earliest appearance of RT‐PCR reaction products in various cell types. Results indicated that P450arom mRNA is detected in round spermatids before it is detected in interstitial cells, whereas 3β‐HSD was detected only in interstitial cells, suggesting that the P450arom mRNA detected in germ cells is not due to interstitial cell contamination of germ cell preparations. Therefore, our results indicate that P450arom mRNA is expressed in adult rat germ cells and that testicular germ cells are a potential source of estrogen in the male reproductive tract.
Potential Involvement of Kallikrein hK2 in the Hydrolysis of the Human Seminal Vesicle Proteins After Ejaculation
Authors: DEPERTHES DAVID , FRENETTE GILLES , BRILLARD‐BOURDET MICHÈLE , BOURGEOIS LUC , GAUTHIER FRANCIS , TREMBLAY ROLAND R. , DUBfé JEAN Y.
Published: October 2023

ABSTRACT: We have recently demonstrated in liquefied human seminal plasma the presence of the novel kallikrein hK2 in association with protein C inhibitor (PCI) as a 75‐kDa complex. In the present study, we showed that hK2, immediately after ejaculation, was recovered only in its free form but complex formation with PCI occurred rapidly thereafter and was completed within 10 minutes. That reaction required an enzymatically active kallikrein. In order to determine the patterns of hydrolysis of major seminal vesicle proteins, semenogelins and fibronectin were exposed to hK2 and to hK3 (prostate‐specific antigen or PSA) and cleavage sequences were identified by N‐terminal sequencing. Free hK2 was able to hydrolyze semenogelins and fibronectin in vitro. Most of cleavage sites were at the carboxyl‐side of arginyl residues. Semenogelins were hydrolyzed to a similar extent by catalytic (and similar) concentration of either hK2 or PSA though no common cleavage sites was identified for both proteinases. Unlike semenogelins, fibronectin was hydrolyzed much more efficiently by hK2 than by PSA. These results show that hK2 is enzymatically active during a short period of time after ejaculation, that major seminal vesicle proteins can be the target of this proteolytic activity, and that hK2 and PSA have different substrate specificities.
Androgens Modulate the α‐Adrenergic Responsiveness of Vascular Smooth Muscle in the Corpus Cavernosum
Authors: REILLY CHRISTOPHER M. , STOPPER VIVIENNE S. , MILLS THOMAS M.
Published: October 2023

ABSTRACT: Rat penile erection is an androgen‐dependent process with castration leading to a loss of potency. The present study was designed to determine if one of the mechanisms by which androgens maintain the erectile response is the regulation of the α‐adrenergic responsiveness of cavemosal smooth muscle. Electrical stimulation of the major pelvic ganglion (MPG) was used to elicit erection in untreated, castrated rats (CASTRATE) or castrated rats given testosterone replacement (TESTO). The effects of phenylephrine (an α1‐adrenergic agonist) and prazosin (an α1‐adrenergic antagonist) on the erectile response were investigated. Phenylephrine, when administered to both TESTO and CASTRATE animals during erection, resulted in a dose‐dependent decrease in the intracavernosal pressure (CCP) with an ED50 value of 1.8 ± 0.48 μg/kg BW for TESTO rats; in the CASTRATE animals, the ED50 was significantly reduced to 0.29 ± 0.08 μg/kg BW. The increases in mean arterial pressure (MAP) resulting from phenylephrine injection in TESTO and CASTRATE animals were of similar magnitude and were not significantly different. Prazosin administration resulted in an enhancement of the erectile response in CASTRATE but not in TESTO animals. Taken together these results demonstrate that the cavemosal vasculature in CASTRATE animals possesses increased reactivity to α‐adrenergic stimulation as compared to the sensitivity in TESTO rats. Based on these findings, we conclude that one of the mechanisms by which androgens maintain erectile function is by regulating the α1‐adrenergic responsiveness of the cavernosal smooth muscle.
The PH‐20 Protein in Human Spermatozoa
Authors: SABEUR KHALIDA , CHERR GARY N. , YUDIN ASHLEY I. , PRIMAKOFF PAUL , LI MING‐WEN , OVERSTREET JAMES W.
Published: October 2023

ABSTRACT: PH‐20 is a sperm plasma‐membrane protein that has been shown to have hyaluronidase activity in several mammalian species including nonhuman primates. In this investigation, the PH‐20 protein was characterized in noncapacitated human sperm and in capacitated human sperm. Two forms of PH‐20 were observed in immunoblots of sodium dodecylsulfate polyacrylamide‐gel electrophoresis (SDS PAGE) using a polyclonal antibody to recombinant PH‐20: a major band of 64 kDa appeared in noncapacitated and capacitated sperm extracts and a 53‐kDa band that appeared only in the acrosome‐reaction supernatant of acrosome‐reacted sperm. Using hyaluronic acid substrate gel analysis, we demonstrated that noncapacitated sperm extracts, capacitated sperm extracts, and the acrosome‐reaction supernatant had hyaluronidase activity at neutral pH (pH 7) and acid pH (pH 4). The 64‐kDa form in all samples had hyaluronidase activity at both neutral and acid pH, but the 53‐kDa form was only active at acid pH. Total hyaluronidase activity, as measured by a microplate assay, was higher at pH 7 than at pH 4. Very low hyaluronidase activity was detected in the acrosome‐reaction supernatant. Transmission electron microscopy and immunogold labeling showed that PH‐20 of acrosome‐intact human sperm was located on the plasma membrane over the entire head but not on the sperm midpiece and tail. After the acrosome reaction, PH‐20 was also located on the inner acrosomal membrane. The biochemical characteristics and the ultrastructural localization of PH‐20 in human sperm suggest that this protein is the human sperm hyaluronidase and, therefore, has an important function during fertilization.
Early Effects of Vasectomy on Testicular Structure and on Germ Cell and Macrophage Apoptosis in the Hamster
Authors: LUE YANHE , HIKIM AMIYA P. SINHA , WANG CHRISTINA , BONAVERA JUAN J. , BARAVARIAN SIMA , LEUNG ANDREW , SWERDLOFF RONALD S.
Published: October 2023

ABSTRACT: This study provides quantitative information on the early (up to 3 months) effects of vasectomy on apoptosis in the hamster testis. Groups of five adult male golden hamsters were either bilaterally vasectomized or sham‐operated and sacrificed at intervals of 3, 6, and 12 weeks after surgery. In all three postvasectomy groups, testis weight and testicular and plasma testosterone (T) levels were not different from controls. Spermatogenic alterations, ranging from tubules with mild intraepithelial vacuoles to almost completely atrophied tubules, were detected in samples of 1 of 5 testes both at 3 and 12 weeks after vasectomy. Histometric analysis of testicular tissues at 3, 6, and 12 weeks in the postvasectomy groups showed no discernible effect of vasectomy on the absolute volumes of seminiferous tubules, tubular lumen, and total Leydig cells when compared to respective controls. In situ analysis of germ‐cell apoptosis, characterized by 3′ ‐end‐labeling immunocytochemistry, revealed a significant increase (2.5‐fold) in germ‐cell apoptosis at stages XIII‐I, involving primarily the dividing spermatocytes after 3 weeks of vasectomy. Apoptotic index was not changed from sham‐operated animals at 6 and 12 weeks postvasectomy. Interestingly, a very high incidence of macrophage apoptosis was detected in the samples of three out of five testes in the 12 weeks postvasectomy group (39.3%) compared to that of controls (0.8%). These results demonstrate that vasectomy has little or no detrimental effect on the morphologic characteristics of the spermatogenesis or intratesticular concentrations of testosterone in the majority of the animals studied up to 12 weeks postsurgery, although vasectomy transiently (3 weeks postsurgery) activated germ‐cell apoptosis, involving dividing spermatocytes at stages XIII‐I.
Spermatids From Mice After Cryptorchid and Reversal Operations Can Initiate Normal Embryo Development
Authors: SASAGAWA ISOJI , YANAGIMACHI RYUZO
Published: October 2023

ABSTRACT: We investigated fertilization and embryo development following intracytoplasmic injection of round spermatids collected from mice after cryptorchid and reversal operations. The rates of oocyte activation, blastocyst formation, and development to live offspring were compared after intracytoplasmic injection of round spermatids from intact, cryptorchid males (control) or males that had undergone the reversal operation. The incidence of normal fertilization and embryo development was about the same when the oocytes were injected with spermatids from intact cryptorchid males or males after reversal operation. The rates of the development of two‐cell embryos to term were also about the same, regardless of the origin of spermatids injected. Round spermatids from both cryptorchid and previously cryptorchid testes can initiate normal embryo development when injected into mature oocytes.
In the Male Brown‐Norway (BN) Male Rat, Reproductive Aging Is Associated With Decreased LH‐Pulse Amplitude and Area
Authors: BONAVERA JUAN J. , SWERDLOFF RONALD S. , LEUNG ANDREW , LUE YAN H. , BARAVARIAN SIMA , SUPERLANO LAURA , SINHA‐HIKIM AMIYA P. , WANG CHRISTINA
Published: October 2023

ABSTRACT: The Brown‐Norway (BN) rat has been proposed as a rodent model for the study of human male reproductive aging. As in man, reduction in serum or plasma testosterone (T) and both testicular (primary) and hypothalamic‐pituitary (secondary) reproductive dysfunction have been associated with aging in male BN rats. However, the presence of secondary testicular failure in this rodent, as indicated by low serum luteinizing hormone (LH) levels, needs further corroboration. The present study was designed to determine whether age‐related differences in the pulsatile patterns of pituitary LH and follicle‐stimulating hormone (FSH) secretion occur in gonad‐intact male BN rats. Three age groups were examined: young (3–4 months), middle aged (12–13 months), and old (21–22 months). Using intra‐atrial cannulae, serial 5‐minute blood samples were withdrawn from conscious, unrestrained animals. Plasma LH concentrations were determined by a supersensitive immunofluorometric assay (FIA) and FSH and T by radioimmunoassay (RIA). Mean T levels were different among groups (young > middle age > old). In young rats, T levels were higher in the late morning/early afternoon than in the late afternoon; this variation was not found in older rats. Mean FSH concentrations were higher in the old than in the middle‐aged and young rats. Significant differences in mean LH levels were not found among groups. Compared to young rats, shortened pulse interval and reduced area of pulses characterized the secretory pattern of both gonadotropins in old rats. In addition, LH‐pulse amplitude and total area of LH pulses were also significantly lower in old than in young rats. Besides the well‐recognized primary testicular failure that occurs in the old BN rat, this study confirms a hypothalamic‐pituitary deficiency that makes this rodent model ideal for studying human male reproductive aging.
Differential Methylation in Steroid 5α‐Reductase Isozyme Genes in Epidydimis, Testis, and Liver of the Adult Rat
Authors: REYES ELSA M. , CAMACHO‐ARROYO IGNACIO , NAVA GABRIEL , CERBÓN MARCO A.
Published: October 2023

ABSTRACT: DNA methylation has been largely involved in the regulation of tissue‐specific gene expression. The aim of the study was to determine the methylation pattern of steroid 5α‐reductase genes 1 and 2 in two reproductive tissues (testis and epidydimis) and a nonproductive tissue (liver) that exhibit different contents of steroid 5α‐reductase isozymes. These isozymes induce the bioconversion of testosterone to dihydrotestosterone that in mammals is a key molecule for external genitalia development. Genomic DNA from the testis, the epididymis, and the liver from normal adult rats was used to determine cytosine and adenine methylation pattern of steroid 5α‐reductase genes 1 and 2 by restriction fragment length polymorphism (RFLP) analysis using restriction enzymes sensitive to adenine (Mbo I and Sau3A I) and cytosine (Hpa II and Msp I) methylation. We also evaluated the expression of both steroid 5α‐reduc‐tase genes by northern blot. When genomic DNA was digested with Hpa II or Msp I, we found that steroid 5α‐reductase gene 2 was less cytosine methylated in the epididymis and in the testis than in the liver. In contrast, when genomic DNA was digested with Mbo I or Sau3A I, we observed that gene 2 was more adenine methylated in the epididymis and in the testis than in the liver. 5α‐Reductase gene 1 presented the same adenine‐ and cytosine‐methylation pattern in the studied tissues. We also found a differential expression of steroid 5α‐reductase genes. Gene 2 was expressed both in the testis and the epididymis but not in the liver; whereas gene 1 was only expressed in the latter. Our results suggest that the differential methylation pattern in 5α‐reductase gene 2 in reproductive and nonreproductive tissues should be involved in the regulation of its expression.
Localization and Effects of Calcitonin Gene‐Related Peptide in the Testicular Vasculature of the Rat
Authors: LISSBRANT ERIK , COLLIN OLA , BERGH ANDERS
Published: October 2023

ABSTRACT: Using laser Doppler flowmetry, the effects of unilateral intratesticular injection of calcitonin gene‐related peptide (CGRP) and CGRP8–37, a CGRP‐receptor antagonist, on right‐and left‐testicular blood flow and mean arterial pressure were studied on anesthetized adult rats. Calcitonin gene‐related peptide in doses of 5 and 50 ng increased blood flow 37 ± 11% (mean ± SEM, P < 0.05) and 30 ± 5% at 5 mm, but not 15 mm, away from the injection site, respectively. They did not influence mean arterial pressure nor blood flow in the contralateral testis. Five‐hundred nanogram doses increased testicular blood flow in the injected testis at a point 15 mm away from the injection site (22 ± 3%, P < 0.05) and caused a slight decrease in mean arterial pressure (‐12 ± 3%, P < 0.05). The highest dose, 5 μg, caused a large (‐39 ± 3%, P < 0.05) fall in mean arterial pressure within 1 minute after injection, and testicular blood flow was reduced in both the injected (‐9 ± 2%, P < 0.05, 15 mm away from injection site) and contralateral testis (‐20 ± 5%, P < 0.05). Pretreatment with 500 ng of the receptor antagonist, CGRP8‐37, did not significantly attenuate the blood flow increasing effect of 50 ng CGRP, nor did 50 μg CGRP8‐37 (given alone) influence basal testicular blood flow in the injected testis. Using immunohistochemistry, CGRP‐containing nerves were observed in the superior and inferior spermatic nerves, in the testicular artery, and in the veins leaving the testis but not in intratesticular blood vessels. Conclusions: 1) CGRP is a potent vasodilator in the testicular vasculature and it may be involved in the local regulation of testicular blood flow; 2) the testis has limited capacity to autoregulate and is consequently unable to maintain a constant testicular blood flow during large and rapid reductions in blood pressure, and 3) the local and systemic effects of vasodilators act in opposite directions in the testis.
The Effects of Gonadotropin‐Releasing Hormone Immunization and Recombinant Follicle‐Stimulating Hormone on the Leydig Cell and Macrophage Populations of the Adult Rat Testis
Authors: DUCKETT RICHARD J. , HEDGER MARK P. , MCLACHLAN ROBERT I. , WREFORD NIGEL G.
Published: October 2023

ABSTRACT: The objective of this study was to investigate the role of the gonadotropins and, in particular follicle‐stimulating hormone (FSH) in maintaining the Leydig cell and macrophage populations of the adult rat testis. Adult male Sprague‐Dawley rats received a gonadotropin‐releasing hormone (GnRH) immunogen for a period of 12 weeks in order to induce a selective deficiency in luteinizing hormone (LH) and FSH. Recombinant human FSH was then administered for 7, 14, and 21 days and macrophages and Leydig cells per testis quantified using the “optical disector” method. After GnRH immunization, Leydig cell and macrophage numbers were reduced by 18% and 68%, respectively, compared with normal controls, resulting in an increase in the ratio of Leydig cells to macrophages from 4:1 to 9:1. Leydig cells regressed morphologically following GnRH immunization, and macrophage mean nuclear diameter was significantly reduced. Administration of FSH did not restore the numbers of either cell type; however, FSH did increase macrophage nuclear size. Eosinophils and mast cells were also found sparsely scattered throughout the interstitium after GnRH immunization and persisted in the FSH‐treated animals. The results of this study indicate that in the adult rat: 1) both Leydig cell and macrophage numbers are reduced in the gonadotropin‐deficient testis; 2) FSH has no effect on the number of either cell type in the absence of LH; and 3) testicular macrophage activity, as indicated by nuclear size, is stimulated by FSH, either directly or indirectly.
The impact of free antiretroviral therapy for pregnant non‐citizens and their infants in Botswana
Authors: Fennell Christina , Escudero Daniel , Zash Rebecca , Diseko Modiegi , Mayondi Gloria , Mabuta Judith , Sekoto Tumalano , Gaolathe Tendani , Mmalane Mompati , Lockman Shahin , Makhema Joseph , Shapiro Roger
Published: October 2023

Introduction

In December 2019, the Botswana government expanded free antiretroviral therapy (ART) to include non‐citizens. We evaluated the impact of this policy change on antenatal care (ANC), antiretroviral therapy coverage and adverse birth outcomes.

Methods

The Tsepamo Surveillance study collects data at up to 18 delivery sites in Botswana. We compared outcomes in citizens and non‐citizens living with HIV before and after antiretroviral therapy expansion to non‐citizens. Adverse birth outcomes included preterm delivery (PTD) <37 weeks, very preterm delivery (VPTD) <32 weeks, small for gestational age (SGA) <10th percentile, very small for gestational age (VSGA) <3rd percentile, stillbirth and neonatal death. Log‐binomial regression models were constructed to generate risk ratios.

Results

From August 2014 to September 2021, 45,576 (96.5%) citizens and 1513 (3.2%) non‐citizens living with HIV delivered; 954 (62.9%) non‐citizen deliveries were before the antiretroviral therapy expansion, and 562 (37.1%) were after. Non‐citizen ANC attendance among pregnant people living with HIV increased from 79.2% pre‐expansion to 87.2% post‐expansion (p<0.001), and became more similar to citizens (96.0% post‐expansion). Non‐citizens receiving any antenatal antiretroviral therapy increased from 65.5% pre‐expansion to 89.9% post‐expansion (p < 0.001), also more similar to citizens (97.2% post‐expansion). Infants born to non‐citizens with singleton gestations in the pre‐expansion period had significantly greater risk of PTD (aRR = 1.28, 95% CI, 1.11, 1.46), VPTD (aRR = 1.89, 95% CI, 1.43, 2.44) and neonatal death (aRR = 1.69, 95% CI, 1.03, 2.60), but reduced SGA risk (aRR = 0.75; 95% CI, 0.62, 0.89) compared with citizens. Post‐expansion, greater declines in most adverse outcomes were observed in non‐citizens, with largely similar outcomes between non‐citizens and citizens. Non‐significant differences were observed for non‐citizenship in PTD (aRR = 0.84, 95% CI, 0.66, 1.06), VPTD (aRR = 0.57, 95% CI, 0.28, 1.01), SGA (aRR = 0.91, 95% CI, 0.72, 1.13), VSGA (aRR = 0.87, 95% CI, 0.58, 1.25), stillbirth (aRR = 0.71, 95% CI, 0.35, 1.27) and neonatal death (aRR = 1.35, 95% CI, 0.60, 2.62).

Conclusions

Following the expansion of free antiretroviral therapy to non‐citizens, gaps narrowed in ANC and antiretroviral therapy use in pregnancy between citizens and non‐citizens living with HIV. Disparities in adverse birth outcomes were no longer observed.
Mechanically stable rifampin antibiotic cement inhibits Pseudomonas aeruginosa biofilm surface growth
Authors: Laperche Jacob , Barrett Caitlin C. , Boduch Abigail , Glasser Jillian , Clippert Drew , Garcia Dioscaris R. , Antoci Valentin
Published: October 2023

Rifampin has been proven to be effective in the treatment of prosthetic infections due to its ability to intercalate into biofilms. The use of rifampin in antibiotic spacers is not well described, which would be especially important in the local periprosthetic environment where parenteral doses have poor penetration. The null hypothesis tests if rifampin use in polymethyl methacrylate (PMMA) cement will show no clinically significant impact on mechanical strength at antibiotic concentrations that remain bactericidal. Test antibiotic cement samples supplemented with 0, 30, 50, 100, 150, or 200 mg of rifampin into a standard 40 g bag were tested for compression to failure using published ASTM standards. The samples were then inoculated with Pseudomonas aeruginosa and either evaluated for lipopolysaccharide (LPS) presence as a marker of biofilm or tested by elution as the Kirby Bauer assay. Rifampin concentrations of 30 and 50 mg, showed no statistically different mechanical characteristics from control PMMA (p > 0.05). The 100‐mg sample fell within the acceptable range of compressive strength and had significantly less LPS and bacterial presence compared to the control at 12 and 24 h. The ability of PMMA with 100 mg of rifampin to maintain its structural integrity and have significant bacterial inhibition at 12 and 24 h makes it a great candidate as an antibiotic bone cement additive. PMMA loaded with up to 100 mg of rifampin shows promise in the treatment and prevention of periprosthetic joint infection for total knee and total hip arthroplasty.
Differences in rice component distribution across layers and their relationship with taste
Authors: Ma Zhao‐hui , Gao Ming‐hui , Cheng Hai‐tao , Song Wen‐wen , Lu Lian‐ji , Lyu Wen‐yan
Published: October 2023

BACKGROUND

Rice taste is closely associated with endosperm composition, which varies among different rice layers. Although clarifying the relationship between this difference and nutritional taste can guide rice breeding and cultivation practices, research on this topic is limited.

RESULTS

Here, typical rice varieties having excellent and poor taste characteristics were selected to analyze the distribution characteristics and differences of their components. The varieties with excellent taste exhibited lower apparent amylose content (AAC) and protein content (PC), lesser short‐chain (Fa) and long‐chain (Fb3) amylopectin (AP) and more medium‐chain (Fb1+2) AP, higher long‐to‐short chain ratio (Fa:Fb3), and higher nitrogen (N), magnesium (Mg) and calcium (Ca) content in layer 1 (L1) than the varieties with poor taste. Layer 2 (L2) played a key role in AAC and PC regulation in the varieties with excellent taste by reducing AAC and appropriately increasing PC, consequently improving rice taste. AP structure in layer 3 (L3) substantially affected the taste of the two types of varieties. The mineral content was the highest in L1, and increased potassium (K), Ca, and Mg content improved taste in all varieties.

CONCLUSION

AAC in each layer contributes to rice taste. PC and minerals primarily act on L1 and L2, whereas AP acts on L2 and L3. Therefore, the endosperm formation process should be exploited for improving rice taste. Furthermore, key resources and cultivation should be identified and regulated, respectively, to improve rice taste. © 2023 Society of Chemical Industry.
Dynamic Interplay Between Kerr Combs and Brillouin Lasing in Fiber Cavities
Authors: Lucas Erwan , Deroh Moise , Kibler Bertrand
Published: October 2023

Highly coherent frequency combs are of crucial importance for optical synthesis and metrology, spectroscopy, laser ranging, and optical communications. Kerr combs, generated via cascaded nonlinear frequency conversion in a passive optical cavity, typically offer high repetition rates, which is essential for some of these applications. Recently, new ways of generating Kerr combs combining Kerr and Brillouin effects have emerged with the aim of improving some performances, especially in the fiber cavity platform. Direct coherent pumping is replaced by lasing on specific cavity modes, offering easily adjustable repetition rates, and enhanced coherence by Brillouin purification. In this study, such a scheme is implemented and investigated in a non‐reciprocal cavity. Highly coherent combs are demonstrated by finely controlling bi‐chromatic Brillouin lasing and the Kerr comb parameters. A suitable numerical model is introduced to account for the interplay between Brillouin scattering, Kerr effect, and cavity resonant feedback. Quantitative agreements with experiments reveal the importance of the pump lasers detuning in setting the comb's properties, through the mode pulling effect. This phenomenon, along with multi‐mode lasing that impedes the coherence, is not studied in previous fiber‐based demonstrations. These limitations are discussed, and several scaling laws are devised.
Multinary Cu─In─Zn─S‐based Quantum‐Dot Electroluminescence and Implications on Device Designs
Authors: Zheng Xiankun , Wang Lijin , Bai Jialin , Zhang Han , Zhang Hanzhuang , Tang Aiwei , Ji Wenyu
Published: October 2023

Currently, the performance of quantum‐dot light‐emitting diodes (QLEDs) based on environmental‐friendly Cu─In─Zn─S quantum dots (QDs) still lags far behind that of Cd‐QDs‐based devices. Here it is demonstrated that the unique trap‐related recombination in Cu─In─Zn─S QDs is mainly responsible for the low device efficiency. The luminous efficiency of Cu─In─Zn─S‐based QLEDs is rather sensitive to the temperature and hole‐transporting layers (HTLs) due to the susceptible thermal‐related trappingdetrapping processes of holes in radiative Cu‐related traps. The holes in Cu‐related traps can be quenched by escaping to the valence band of the QDs or/and transferring to the adjacent HTLs. An HTL with low highest occupied molecular orbitals is desired to enhance the hole injection and hinder the aforementioned hole transfer. As a result, a high device efficiency of 6.0 cd A−1 is achieved at room temperature, which is attributed to suppressed HTL‐induced emission quenching and efficient valence‐band‐dominated hole injection from HTL to the QDs. The device efficiency is further increased to 13.2 cd A−1 at 150K by suppressing thermal‐induced quenching.
Polymeric conjugates of drugs and antibodies for site‐specific drug delivery
Authors: Ulbrich Karel , Strohalm Jiří , Šubr Vladimír , Plocová Dana , Duncan Ruth , Říhová Blanka
Published: October 2023

The synthesis of targetable conjugates of doxorubicin bound to N‐(2‐hydroxypropyl)methacrylamide copolymers was investigated. Anti‐CD3 antibody against TCR/CD3 complex was used to target the conjugates to T‐cells. The effect of structure of the oligopeptide spacer between the drug and polymer as well as of the polymer modification with the antibody on the rate of drug release from the polymeric carrier system incubatedin vitrowith cathepsin B or with a mixture of intracellular enzymes (tritosomes) is discussed. The results ofin vitrodrug‐release experiments are correlated with the evaluation of T‐cell cytotoxicity of targeted and nontargeted polymer‐bound doxorubicin conjugates measuredin vitroas the inhibition of Con‐A stimulated growth of human peripheral blood lymphocytes (3H‐thymidine incorporation method).
A Propolis‐Derived Small Molecule Tectochrysin Ameliorates Type 2 Diabetes in Mice by Activating Insulin Receptor β
Authors: Zhang Jianfeng , Wu Jiangwei , Shi Xiaochen , Li Defu , Yang Shizhen , Zhang Ruixin , Xia Bo , Yang Gongshe
Published: October 2023

Scope

Propolis has been found to decrease glucose levels and increase insulin sensitivity in type 2 diabetes. However, the active ingredient responsible for these effects and its regulating mechanism are not fully understood.

Methods and results

To address this, molecular docking screening is used to screen the effective hypoglycemic ingredient in propolis and found that tectochrysin (TEC) has a high affinity to the insulin receptor (IR), highlighting its potential for glycemic control. In vivo tests show that TEC decreases glucose levels and enhances insulin sensitivity in db/db mice. By hyperinsulinemic euglycemic clamp test, this study further finds that TEC promotes glucose uptake in adipose tissue and skeletal muscle, as well as inhibits hepatic gluconeogenesis. Moreover, it finds that TEC promotes glucose uptake and adipocytes differentiation in 3T3‐L1 cells like insulin, suggesting that TEC exerts an insulin mimetic effect. Mechanistically, pharmacology inhibition of IRβ abolishes the effects of TEC on glucose uptake and the phosphorylation of IR. The study further demonstrates that TEC binds to and activates IRβ by targeting its E1077 and M1079.

Conclusion

Therefore, this study sheds light on the mechanism underlying propolis’ potential for ameliorating type 2 diabetes, offering a natural food‐derived compound as a promising therapeutic option.
Nanonet membranes with nano‐mastoid structure for high‐performance oily wastewater treatment
Authors: Chen Yu , Tang Jianwei , Zhu Weiyan , Wu Xunhuang , Pan Tiandi , Tang Ning , Zhang Yong
Published: October 2023

The pollution caused by oily wastewater has a severe influence on the human health and ecological environment. However, the present membranes suffer from a bottleneck that it is difficult to synchronously improve the filtration efficiency and permeation flux. It is still of great importance to develop efficient oil‐in‐water separation membranes. Herein, we have prepared a nanonet membrane (NM) with both nanonet structure and nano‐mastoid structure through a combination of phase inversion with electrospinning. Profiting from the structural advantages of network interconnectivity, sub‐micrometer pores, and high porosity, the NMs demonstrated outstanding capacity for separating nanoscale oil‐in‐water emulsions with a prospective separation efficiency (99.2%) and robust permeation flux (24,076 L m−2 h−1). Importantly, benefitting from their good surface wettability and low underwater oil adhesion, the NMs maintained a stable permeation flux (7738 L m−2 h−1) and stable high separation efficiency (99.1%) even after 10 separation cycles. The synthesis of such nanonet membranes may develop new paths for the development of next‐generation separation membranes with high performance.
The influence of individual evaluation of electron‐impact ionization, attachment, and photoionization rates on positive streamer propagation
Authors: Wei Zhenyu , Komuro Atsushi , Ono Ryo
Published: October 2023

This study evaluates the individual effects of electron‐impact ionization, attachment, and photoionization on streamer propagation to provide a deeper understanding of the streamer propagation mechanism and useful knowledge to obtain the best set of input data for verification and validation studies. The results show that streamers with higher electron‐impact ionization rates have higher propagation velocities and lower electric fields, while those with higher attachment rates have slower propagation velocities and higher electric fields. Streamers with higher photoionization rates have lower electric fields at the head, but the velocity remains largely unaffected. The effects of different rates of ionization, attachment, and photoionization have been analyzed using an analytical solution called the diameter‐speed relation.
Severe lung disease in children with cystic fibrosis missed in newborn screening
Authors: Baldwin Kathrine , Barker Erin McElroy , Carayannopoulos Mary , Farrell Philip M. , Zanni Robert , Scanlin Thomas F.
Published: October 2023

Background

Cystic fibrosis (CF) is now routinely diagnosed through newborn screening (NBS), but the tests employed in the USA have been evolving for two decades as missed cases become recognized and lab methods improve in association with more knowledge about CF genetics. New Jersey was among the first states to implement CF NBS in 2001 when it introduced the original two‐tiered method that combined measurements of immunoreactive trypsinogen (IRT) with detection of the principal pathogenic variant (F508del) in the cystic fibrosis transmembrane conductance regulator (CFTR) gene.

Objective

With continuation of the IRT/DNA (F508del) algorithm for two decades and identification of screening false negative children, we decided to examine the condition of some missed cases with special attention to their respiratory status.

Methods

To strengthen the arguments for quality improvement in New Jersey's CF NBS program, we reviewed and evaluated false negative cases to determine the potential extent of preventable patient suffering as a consequence of delayed diagnoses.

Results

Five children with CF who had false negative screening results were studied in detail. In each case there was a different cause of the negative screening results. They all had clinically significant/severe lung disease, ranging from chronic cough with CF pathogens on respiratory culture at a young age to respiratory failure.

Conclusion

This case series highlights the consequences of false negative screening results, which served as the impetus to upgrade New Jersey's CF NBS algorithm. Implemented changes include lowering the IRT cutoff to 70 ng/mL and expanding to a 139 variant CFTR panel. In 2023, a floating IRT cutoff is anticipated to be implemented.
Seasonal differences in tropical cyclone—induced sea surface cooling in the western North Pacific
Authors: Singh Vineet Kumar , Kim Hye‐Ji , Moon Il‐Ju
Published: October 2023

Tropical cyclone (TC)‐induced sea surface temperature (SST) cooling plays an important role in controlling the intensity of TCs in ocean basins and can modulate the local weather. This study examined the seasonal differences in TC‐induced SST cooling, especially between summer (June–August) and autumn (September–November), in the western North Pacific for the period 1992–2021. The analysis shows that the average maximum TC‐induced SST cooling along the TC track in autumn is 0.18°C less than in summer, although the mean TC intensity in autumn is 14 knots higher than in summer. This is because in autumn, the average mixed‐layer depth is 10–13 m deeper than in summer, and the TC track shifts equatorward, preventing the entrainment of cooler subsurface water to the surface, thereby causing less SST cooling in autumn at the same TC intensity. Given the negative feedback of TC‐induced SST cooling on TC intensity, these results are crucial to understand the seasonal differences in the intensity of TC in this basin.