bluuebunny/crossref_metadata_2025 huggingface dataset:
A Statistical and Clinical Evaluation of Fingerstick and Routine Laboratory Prothrombin Time Measurements
Authors: Bussey Henry I. , Chiquette Elaine , Bianco Theresa M. , Lowder‐Bender Kathryn , Kraynak Maura A. , Linn William D. , Farnett Lisa , Clark Gary M.
Published: October 2023

Study Objective. To compare prothrombin time measurements by fingerstick and routine laboratory methods.

Design. Prospective cohort study.

Setting. University‐affiliated anticoagulation clinic.

Patients. Thirty‐three patients receiving warfarin with stable anticoagulation for 3 months preceding the two studies.

Interventions. Groups 1 (17 patients) and 2 (16 patients) provided 150 and 125 paired samples, respectively, for fingerstick and routine laboratory analysis. The fact that no patient required a dosage change allowed for a clinical assessment.

Measurements and Main Results. Correlation and agreement between methods were good in group 1 but poor in group 2. Fingerstick results were less variable (smaller standard deviation and smaller coefficient of repeatability) in both groups. By analysis of discrepant pairs (25 in group 1, 63 in group 2), the routine laboratory results indicated dosage changes erroneously more often than did the fingerstick method.

Conclusions. In these two trials, the fingerstick system was superior to the routine laboratory method in that it was more reliable (less variability and more repeatable) and less likely to indicate dosage changes erroneously. (Pharmacotherapy 1997;17(5):861–866)

Conclusions: Although it is entirely feasible that RL and FS comparisons in other locations might differ from those presented here, it is important that any such comparison go beyond calculating a correlation coefficient. Additionally, any such evaluation should take into account that the “gold standard” (the RL) may be the inferior method. While there are a number of potential explanations as to why data from groups 1 and 2 were not more similar, the fact remains that under the conditions of the two trials, the FS method demonstrated less variability, was more repeatable, and was less likely to indicate dosage changes erroneously than was the RL method in either the hospital or clinic laboratory of a large university health science center. The FS system was superior to either RL.
Comparison of 5‐Fluorouracil Pharmacokinetics in Whole Blood, Plasma, and Red Blood Cells in Patients with Colorectal Cancer
Authors: Wattanatorn Wiboon , McLeod Howard L. , Macklon Fiona , Reid Muriel , Kendle Keith E. , Cassidy James
Published: October 2023

Study Objective. To compare 5‐fluorouracil (5‐FU) pharmacokinetics in whole blood, plasma, and red blood cells in patients with colorectal cancer.

Design. Prospective, unblinded observational study in consecutive patients.

Setting. Large regional teaching hospital.

Patients. Five patients with colorectal cancer.

Interventions. Patients received folinic acid 200 mg/m2 intravenously over 2 hours, followed by 5‐FU 600 mg/m2 intravenous bolus over 30 minutes, then 5‐FU 600 mg/m2 intravenous infusion over 22 hours, administered on days 1 and 2. This 48‐hour cycle was repeated every 14 days.

Measurements and Main Results. Concentrations of 5‐FU in whole blood, plasma, and red blood cells were determined by high‐performance liquid chromatography. ADAPT II was used for pharmacokinetic computations. The optimum model was determined for each matrix by calculating Akaike's information criteria values. Concentrations of 5‐FU in whole blood were 106–115% of simultaneous plasma concentrations (median 112%), and packed red blood cell levels were 5–17% of plasma concentrations (median 11%). The drug's concentration‐time profile was similar in the three matrices. The drug is reported to be unstable in whole blood, and red blood cell 5‐FU concentrations were near the limit of detection (10 ng/ml), supporting plasma as the preferred matrix for therapeutic drug monitoring studies. Six pharmacokinetic models were fitted to the 5‐FU individual data sets to determine the best curve fit. The optimal model for whole blood and plasma data sets was one compartment with both linear and nonlinear elimination models; a one‐compartment model with nonlinear elimination provided the best curve fit for 5‐FU in red blood cells. A two‐compartment model with nonlinear elimination gave a similar degree of curve fit for plasma 5‐FU as the one‐compartment model with both linear and nonlinear elimination.

Conclusions. These pharmacokinetic results provide the basis for further investigation into the ability to correlate 5‐FU systemic exposure with clinical drug activity. (Pharmacotherapy 1997;17(5):881–886)
Retrospective Evaluation of Therapies for Staphylococcus aureus Endocarditis
Authors: Gentry Chris A. , Rodvold Keith A. , Novak Richard M. , Hershow Ronald C. , Naderer Odin J.
Published: October 2023

We retrospectively evaluated antiinfective therapy for methicillin‐sensitive (MSSA) and methicillin‐resistant Staphylococcus aureus (MRSA) endocarditis in 54 patients who had 57 treatment courses for the disease. Three treatments were assessed: 27 nafcillin‐treated courses of MSSA endocarditis, 18 vancomycin‐treated courses of MSSA endocarditis, and 11 vancomycin‐treated courses of MRSA endocarditis. At baseline, patients with MSSA treated with vancomycin had more chronic conditions (p<0.01), a lower frequency of intravenous drug use (p<0.01), a lower hematocrit concentration (p<0.05), and a higher serum creatinine concentration (p<0.05) than the nafcillin group. Vancomycin‐treated patients had a higher complication rate during therapy (p<0.05) and a longer duration in an intensive care unit (p<0.01) than the nafcillin group. The trend was for a higher complete response rate in the nafcillin group (74% vs 50%, p=0.12), but no difference in mortality (22% vs 28%, p=0.73). Patients with MRSA infection treated with vancomycin had higher mortality than those with MSSA who received that drug (55% vs 28%, p=0.24). Patients with vancomycin‐treated MSSA endocarditis may have a poorer outcome than those who receive nafcillin, but this may be influenced by different or more severe clinical features. (Pharmacotherapy 1997;17(5):990–997)
Fluconazole Serum Concentrations and Pharmacokinetics in an Obese Patient
Authors: Cohen Louise Glassner , DiBiasio Alan , Lisco Steven J. , Hurford William E.
Published: October 2023

Current fluconazole dosing recommendations are based on pharmacokinetic parameters calculated from serum concentration data in subjects and patients of normal weight. These recommendations may be inaccurate when applied to obese individuals due to the physiologic changes of obesity that may influence drug pharmacokinetics. A 39‐year‐old morbidly obese man (BMI 48.3 kg/m2) was treated with fluconazole 1200 mg/day infused over 6 hours. After 14 days of therapy, blood samples were obtained at 0, 1, 2, 4, 8, 12, 18, and 24 hours after infusion and steady‐state serum concentrations were determined using a bioassay. Pharmacokinetic parameters calculated were area under the concentration‐time curve (AUC0‐24) 574.9 mg/L*hour, average steady‐state serum concentration 23.9 mg/L, and fluconazole clearance 139.4 ml/minute. Compared with published data, our patient had a lower area under the curve and increased fluconazole clearance. These changes may be due to the drug's increased volume of distribution. Based on these data and the favorable toxicity profile of fluconazole, we recommend considering higher dosages in such morbidly obese patients.
Methylprednisolone Disposition Kinetics in Patients with Acute Spinal Cord Injury
Authors: Segal Jack L. , Maltby Brian F. , Langdorf Mark I. , Jacobson Ray , Brunnemann Sherry R. , Jusko William J.
Published: October 2023

Study Objective. To evaluate the pharmacokinetics of high‐dose methylprednisolone in patients with acute spinal cord injury (ASCI).

Design. Open‐label study of consecutive patients with ASCI, and retrospective review of able‐bodied controls.

Setting. Emergency Medicine Department of a large, urban, university‐affiliated, tertiary care trauma center.

Patients. Eleven men with ASCI.

Interventions. Methylprednisolone sodium succinate 30 mg/kg intravenous bolus, followed by 5.4 mg/kg/hour for 23 hours, administered according to the second National Acute Spinal Cord Injury Study (NASCIS 2) protocol.

Measurements and Main Results. The total systemic clearance of methylprednisolone was significantly less in acutely injured patients (mean ± SD 30.04 ± 12.03 L/hr) than in historically reported able‐bodied controls (44.70 ± 4.90 L/hr). An inverse correlation between the neurologic level of injury and systemic clearance was seen. No differences in volume of distribution were discernible between patients (126.90 L) and controls (135.45 L).

Conclusion. Patients with acute spinal cord injury administered methylprednisolone according to the NASCIS 2 protocol had an apparent decrease in total systemic clearance of the drug without a commensurate change in volume of distribution. Additional studies are warranted to confirm these findings and assess the potential impact of diminished clearance on the efficacy of the agent in ASCI.
Interaction Between Cyclosporine and Grapefruit Juice Requires Long‐Term Ingestion in Stable Renal Transplant Recipients
Authors: Brunner Lane J. , Munar Myrna Y. , Vallian John , Wolfson Marsha , Stennett Douglass J. , Meyer Mary M. , Bennett William M.
Published: October 2023

Study Objective. To examine the effect of the concurrent administration of increasing amounts of grapefruit juice, an inhibitor of drug metabolism, on the steady‐state pharmacokinetics of cyclosporine.

Design. Open‐label, three‐period crossover, food‐drug interaction study in stable renal transplant patients.

Setting. A university‐affiliated clinical research center.

Patients. Sixteen stable renal transplant recipients.

Intervention. Cyclosporine was administered with 240 ml of water, 240 ml of grapefruit juice, or several 240‐ml glasses of grapefruit juice, and serial blood samples were taken to estimate the effect of grapefruit juice on cyclosporine pharmacokinetics.

Measurements and Main Results. Grapefruit juice caused a significant increase in cyclosporine area under the curve, however, no significant effect was seen in other pharmacokinetic parameters. Grapefruit juice caused an increase in the 24‐hour trough cyclosporine concentration, which may be of clinical significance if long‐term ingestion of grapefruit juice is recommended.

Conclusion. A drug interaction exists between cyclosporine and grapefruit juice, and it is likely at the level of intestinal drug absorption.
Pharmacoeconomic Analysis of Ampicillin‐Sulbactam versus Cefoxitin in the Treatment of Intraabdominal Infections
Authors: Messick Chad R. , Mamdani Muhammad , McNicholl Ian R. , Danziger Larry H. , Rodvold Keith A. , Condon Robert E. , Walker Alonzo P. , Edmiston Charles E.
Published: October 2023

We conducted a retrospective pharmacoeconomic analysis of a prospective, multicenter, double‐blind, randomized, controlled trial comparing the β‐lactamase inhibitor combination ampicillin‐sulbactam (96 patients) and the cephalosporin cefoxitin (101) in the treatment of intraabdominal infections. An institutional perspective was adopted for the analysis. The primary outcomes of interest were cure and failure rates, development of new infection, and antibiotic‐related adverse events. Epidemiologic data pertaining to outcomes was retrieved primarily from the trial, although results of other published studies were taken into consideration through extensive sensitivity analyses. Data pertaining to potential resource use and economic impact were retrieved mainly from the University Health Consortium and hospital‐specific sources. When considering only costs associated with drug acquisition through cost‐minimization analysis, a potential savings of $37.24/patient may be realized with ampicillin‐sulbactam relative to cefoxitin based on an average 7‐day regimen. Outcome data collected for the entire hospitalization during the trial revealed an approximately 9% greater frequency of failure with cefoxitin relative to ampicillin‐sulbactam. When considering all outcomes of interest in the initial base‐case analysis, a potential cost savings of approximately $890/patient may be realized with ampicillin‐sulbactam relative to cefoxitin. In assessing the impact of the significant variability in probability and cost estimates, Monte Carlo analysis revealed a savings of $425/patient for ampicillin‐sulbactam over cefoxitin (95% CI $618–1516). Given the model assumptions, our analysis suggests a 78% certainty level that savings will be experienced when ampicillin‐sulbactam is chosen over cefoxitin.
Analytic and Clinical Performance of Two Compact Cholesterol‐Testing Devices
Authors: Volles David F. , McKenney James M. , Miller W. Greg , Ruffen David , Zhang Dongbo
Published: October 2023

Several relatively inexpensive compact analyzers for measuring cholesterol are available for use outside of the clinical laboratory. We evaluated the analytic and clinical performance of total cholesterol assayed with the AccuMeter (ChemTrak) and the LDX (Cholestech). Accuracy of both devices was evaluated by collecting capillary and venous whole blood from 100 subjects and assaying for total cholesterol. Results were compared with the Centers for Disease Control standardized reference laboratory method. Mean percent bias, mean absolute percent bias, and percentage of subjects with total error above ± 8.9% were calculated and results were compared with recommendations from National Cholesterol Education Program (NCEP) for total cholesterol measurements. Precision was evaluated by assay of three pooled serum samples with both devices in duplicate in two runs/day for 20 days. The CV for each serum pool for each device was calculated and compared with NCEP recommendations for precision for total cholesterol measurements. Results with the two devices were compared. The total cholesterol mean percent bias for capillary samples was 2.1% for the LDX and −1.0% for the AccuMeter (p<0.01), and for venous samples 1.6 and −2.0%, respectively (p<0.001). The mean absolute percent bias for capillary samples was 5.4 and 5.2%, respectively (p=0.29), and for venous samples was 5.0 and 5.7% (p=0.79). Each device had an excessive number (12–22%) of individual results that exceeded NCEP recommended total error for a single cholesterol measurement (± 8.9%). In the precision analysis the average CV from all three serum pools was 4.0% and 5.3% for the LDX and AccuMeter, respectively (p<0.05). Thus both devices failed to meet the NCEP recommendation for precision of 3% CV. They both provided total cholesterol results that correctly classified individual patients into appropriate risk groups 95% of the time or better if values within ± 8.9% of NCEP cut points for risk classification were ignored. Both devices met the NCEP ± 3% requirement for total cholesterol mean percent bias but did not meet the ± 3% requirement for CV as a measure of precision. Because of the variability in results, both devices had excessive numbers of individual subjects with total cholesterol results greater than the recommended total error limit of ± 8.9% difference from the standardized method. Despite variability in some individual results, the rate of clinical misclassifications for coronary heart disease risk was relatively low for both devices if results near the NCEP cut points were repeated.
Accuracy of Tablet Splitting
Authors: McDevitt Joseph T. , Gurst Andrea H. , Chen Yinshuo
Published: October 2023

We attempted to determine the accuracy of manually splitting hydrochlorothiazide tablets. Ninety‐four healthy volunteers each split ten 25‐mg hydrochlorothiazide tablets, which were then weighed using an analytical balance. Demographics, grip and pinch strength, digit circumference, and tablet‐splitting experience were documented. Subjects were also surveyed regarding their willingness to pay a premium for commercially available, lower‐dose tablets. Of 1752 manually split tablet portions, 41.3% deviated from ideal weight by more than 10% and 12.4% deviated by more than 20%. Gender, age, education, and tablet‐splitting experience were not predictive of variability. Most subjects (96.8%) stated a preference for commercially produced, lower‐dose tablets, and 77.2% were willing to pay more for them. For drugs with steep dose‐response curves or narrow therapeutic windows, the differences we recorded could be clinically relevant.
Phenytoin Toxicity in an Older Patient with Slow Metabolism and Atypical Presentation
Authors: Pitner Janet K. , Long Lesle D. , Meyer Reneé P. , Pennypacker Leslye C.
Published: October 2023

Phenytoin toxicity occurred in an older man who received a dosage of 300 mg/day. The patient developed high serum phenytoin concentrations from this common adult dosage, with symptoms of functional decline and altered mental status. These behaviors were perceived as sun‐downing and were treated with haloperidol. A long hospitalization was required.
Importance of Bicarbonate to the Progesterone‐initiated Human Sperm Acrosome Reaction
Authors: SABEUR KHALIDA , MEIZEL STANLEY
Published: October 2023

ABSTRACT: Progesterone, a putative in vivo initiator of the human sperm acrosome reaction (AR), has previously been shown to act at the sperm plasma membrane to initiate the AR in vitro. Here, we have investigated whether bicarbonate (HCO3‐) was required for the progesterone‐initiated human AR and whether HCO3‐ ‐dependent cAMP activation might be involved. Capacitated human sperm were suspended in the presence of high (25 mM) or low (1 mM) HCO3 media. The AR was assayed using fluorescein isothiocyanate (FITC)‐conconavalin A with sperm fixed 5 minutes after progesterone or solvent control addition. Progesterone initiated the AR in both high and low HCO3‐ media, but the percentage of AR was significantly lower in the latter medium. In the presence of high HCO3‐, 20‐minute preincubation with 4,4′‐diisothiocyanostilbene‐2,2′‐disulfonic acid (DIDS), a blocker of HCO3‐ transport, inhibited the progesterone‐initiated AR in a dose‐dependent manner. The maximum inhibition (85%) was obtained with 18 μM DIDS. Inhibition by DIDS was reversed by washing sperm after treatment. Preincubation of sperm with dibutyryl cAMP (0.1 μM‐1 mM) plus DIDS almost completely eliminated the inhibition of the progesterone‐initiated AR by DIDS. Dibutyryl cAMP alone did not have a stimulatory effect on the progesterone‐initiated AR, when high HCO3‐ was present, but it was able to partially overcome the reduction of AR by low HCO3. These results are the first to demonstrate the importance of HCO3‐ to: 1) mammalian AR initiation by the putative physiological initiator progesterone, and 2) the human sperm AR. Furthermore, they suggest that HCO3‐ transport and HCO3‐ stimulation of adenylate cyclase are involved in the mechanism of the progesterone‐initiated human AR.
Morphometric Study of the Gubernaculum in Male Estrogen Receptor Mutant Mice
Authors: DONALDSON KAREN M. , TONG STEVEN Y. C. , WASHBURN TODD , LUBAHN DENNIS B. , EDDY EDWARD M. , HUTSON JOHN M. , KORACH KENNETH S.
Published: October 2023

ABSTRACT: To determine role of estrogen receptors in testicular descent, a morphometric study of the testis and structures derived from the gubernaculum was made in sexually mature male mice having an estrogen receptor disrupted gene mutation (ERKO). Macroscopic dissections and sagittal serial sections were made of the pelvis of four wild‐type mice, four mice heterozygous for the ERKO mutation, and four homozygous ERKO males. By external morphological examination the testes appeared to be descended in all three genotypes. All mice had development of a cremaster sac, which is derived from the gubernaculum, but this was twice as large in wild‐type mice than in both the heterozygote or homozygote ERKO groups.

The cause for the smaller cremaster sac appeared to be excessive development of the cremaster muscle in ERKO mice. The thickened muscle was associated with postmortem retraction of the testes into the inguinal canal or abdomen. Spermatogenesis and testicular volume were deficient in homozygous ERKO mice at this age. This study demonstrates that estrogen has a previously unknown role in masculine sexual development of the gubernaculum and the structures derived from it, such as the cremaster muscle.
Ultrastructural and Immunohistochemlcal Characterization of the Tunica Albuginea in Peyronie's Disease and Veno‐occlusive Dysfunction
Authors: GENTILE VINCENZO , MODESTI ANDREA , LA PERA GIUSEPPE , VASATURO FORTUNATA , MODICA ALESSANDRO , PRIGIOTTI GIANRICO , DI SILVERIO FRANCO , SCARPA SUSANNA
Published: October 2023

ABSTRACT: The tunica albuginea and corpus cavernosum from patients with Peyronie's disease (PD), patients with veno‐occlusive dysfunction (VOD), and those from normal control subjects were studied by transmission electron microscopy and immunohistochemical staining for type I, III, and V collagens, platelet‐derived growth factor (PDGF) AA and BB homodimers, and PDGF alpha and beta receptors. Ultrastructural modifications resembling a fibrotic reaction were detected in the two pathological tunica albuginea, but not in those from control subjects. Ultrastructural data demonstrated a general increase in fibrous and amorphous extracellular matrix material in the pathological tunica albuginea. The amorphous material probably represents glycoproteins and proteoglycans. The fibrous material, representing collagen, appears disorganized in the tissue and does not display the typical and homogeneous diameter, size, and spatial arrangement. Large areas of extracellular and intracytoplasmic, partially degraded, fibers are visible. An increased type I/III collagen ratio was detected by immunohistochemistry in the two pathological tunica albuginea. Moreover, a strong expression of type V collagen, correlated to fibroblasts, was revealed. Fibroblasts from control tissues, on the other hand, were totally negative. Finally, PDGF AA and BB were positive in fibroblasts from pathological tunica albuginea but were negative in control tissues. PDGF beta receptor was positive in pathological and normal tissue fibroblasts. Tunica albuginea from PD and VOD show similar ultrastructural and immunohistochemical alterations, whereas the corpus cavernosum shows no visible modifications.
Regulation of the Epididymal Synthesis of P26h, a Hamster Sperm Protein
Authors: BéRUBË BRUNO , LEFIËVRE LINDA , COUTU LOUISE , SULLIVAN ROBERT
Published: October 2023

ABSTRACT: We have previously identified a 26‐kDa epididymal hamster sperm glycoprotein (P26h) that is involved in gamete interaction. This protein is added to the acrosomal cap during epididymal transit of spermatozoa. Because the epididymis secretes proteins under androgen control, the aim of this study was to document the testicular control of the epididymal ontogenesis of P26h. The cytosolic fraction of the epididymides of male hamsters of different ages, prepared by ultracentrifugation, was used as well as those from mature males at different times following castration. These extracts were Western blotted and probed with an anti‐P26h antiserum. P26h was initially immunodetectable in extracts prepared from hamsters 4 weeks of age, and the signal increased up to the 7th week of age. The P26h signal decreased rapidly after castration until the antigen was undetectable at 3 days following castration. Administration of testosterone to 3‐week‐old male hamsters resulted in the epididymal expression of P26h earlier than that observed in untreated or control animals. These results suggest that P26h protein expression in hamster epididymis is under testicular androgen control.
Effects of Endothelin‐1 on the Rat Testicular Vasculature
Authors: COLLIN OLA , DAMBER JAN‐ERIK , BERGH ANDERS
Published: October 2023

ABSTRACT: Endothelin‐1 (ET‐1), a well‐known vasoconstrictor substance, is present in the testis but its functional role is unknown. The present study was undertaken to elucidate whether ET‐1 may influence testicular blood flow. ET‐1 (0.1, 1, 10, 100 ng), an ETA antagonist (BQ123; 0.01, 1, 100 μg), or saline were administered by intratesticular injections (0.1 ml) in adult rats. The effect on testicular blood flow was monitored using a laser Doppler flowmeter. The localization of immunoreactive ET‐1 (irET‐1) was studied by immunohistochemistry and the testicular irET‐1 concentration was measured in normal and human chorionic gonadotrophin (hCG)‐treated rats using a radioimmunoassay. ET‐1 injection, in a dose‐related way acutely decreased testicular blood flow and this effect was blocked by an ETA antagonist. The antagonist itself did not, however, influence testicular blood flow. Accumulation of polymorphonuclear leukocytes was observed in testicular venules 2 hours after ET‐1 injection. Immunoreactive ET‐1 was observed in Leydig, Sertoli, and endothelial cells. The testicular irET‐1 content was increased 2‐fold by hCG stimulation but local injection of the ET‐1 antagonist did not influence testicular blood flow in hCG‐treated rats. The present study suggests that ET‐1 could be a hormonally regulated and locally produced modulator of testicular blood flow and microcirculation.
Sperm Autoantigens Recognized by Autoantibodies in Developing Rats Following Prepubertal Obstruction of the Vas Deferens
Authors: FLICKINGER CHARLES J. , BARAN MAUREEN L. , HOWARDS STUART S. , HERR JOHN C.
Published: October 2023

ABSTRACT: Sperm protein autoantigens recognized by serum antisperm autoantibodies during development following vas deferens obstruction were studied using western blot analysis. At age 10 days, rats in an obstructed group underwent bilateral ligation and division of the vas deferens, whereas animals assigned to a sham group received a sham operation. At ages 14, 21, 35, 56, 91, and 128 days, rats were sacrificed and blood samples were obtained. Sperm antigens were recognized infrequently and with low intensity by most sera obtained at ages 14 through 56 days. Subsequently, the incidence as well as the intensity of staining of antigens in blots increased at 91‐and 128‐day intervals in obstructed animals. The increase in antisperm antibodies correlated with the appearance of sperm throughout the epididymis at approximately 56 days postnatally. A set of autoantigens including proteins migrating at 82‐78, 76‐73, 68, 57, 54, 48, 44, 42, 38–42, 36, and 22 kDa were recognized with the highest frequency and intensity after puberty. A 42‐kDa protein appeared to be one of the first autoantigens recognized when obstructed animals underwent sexual maturation. Although individual animals recognized different patterns of sperm autoantigens, a repertoire of 10–12 autoantigens dominated the antisperm antibody response when obstructed animals underwent sexual maturation.
Ultrastructural Observations of Spermatogenesis Following Transplantation of Rat Testis Cells Into Mouse Seminiferous Tubules
Authors: RUSSELL LONNIE D. , BRINSTER RALPH L.
Published: October 2023

ABSTRACT: The testes of busulfan‐treated immunodeficient mice receiving seminiferous tubuie injections of testis cells from rats were examined by light and electron microscopy. The presence of active rat spermatogenesis was verified by criteria that are known to characterize spermatogenic cells of this species. In addition, spermatogenesis from the mouse was identified as taking place in some seminiferous tubules as the result of reinitiation of spermatogenesis after busulfan treatment. Rat spermatogenesis in mouse seminiferous tubules showed the generally recognized associations of cells known to characterize stages of spermatogenesis of the rat. The Sertoli cells associated with rat spermatogenesis were identified ultrastructurally as being of mouse origin. Thus, rat spermatogenesis, which has a cycle length that is 50% longer than mouse spermatogenesis, can proceed among mouse Sertoli cells, which supposedly exert much shorter cyclic influences in concert with mouse germ cell development. Studies are needed to determine if the timing of rat spermatogenesis is controlled by the germ cells or the Sertoli cells. These observations are considered preliminary since a thorough study of somatic‐germ cell relationships was not undertaken. It is concluded that a mouse Sertoli cell in the environment provided by the mouse testis can produce both mouse and rat gametes.
Isolation of Highly Purified Type A Spermatogonia From Prepubertal Rat Testis
Authors: MORENA ANNA RITA , BOITANI CARLA , PESCE MAURIZIO , de FELICI MASSIMO , STEFANINI MARIO
Published: October 2023

ABSTRACT:We have developed a new method that allows isolation of highly purified type A spermatogonia from prepubertal rats. The procedure is based on the maximal release of spermatogonia from the seminiferous epithelium obtained by the complete enzymatic digestion of the tubular basal lamina, followed by removal of contaminating somatic cells through adhesion to plastic dishes coated with the lectinDatura stramoniumagglutinin and fractionation on a discontinuous Percoll gradient. The cell suspension obtained contains up to 85% type A spermatogonia. Besides morphological criteria, the identification of germ cells and somatic cells has been performed by means of immunocytochemical markers, such asc‐kitreceptor, which is present only in germ cells, and vimentin, which is present only in somatic cells. All type A spermatogonia isolated werec‐kitpositive, thus suggesting thatc‐kitreceptor is present in both undifferentiated and differentiating type A spermatogonia. Preliminary culture experiments demonstrate that spermatogonia survivalin vitrowas significantly improved by the addition of 10% fetal calf serum or horse serum to the culture medium; however, optimal culture conditions remain to be established.In vitrostudies on isolated spermatogonia may provide a significant contribution toward elucidation of the mechanisms regulating spermatogonial proliferation and differentiation.
The Influence of Semen Analysis Parameters on the Fertility Potential of Infertile Couples
Authors: AYALA CARMA , STEINBERGER EMIL , SMITH DAVID P.
Published: October 2023

ABSTRACT: The objective of this study was to investigate the relationship between couples' fertility potential and several parameters of semen analysis (from a single semen sample/male partner) in a cohort of 1,055 infertile couples seen at the Texas Institute for Reproductive Medicine and Endocrinology for a total of 9,409 follow‐up months. The medians of sperm concentrations (SC), total sperm counts (TSC), percent motility (MOT), motile sperm concentrations (MSC), and total motile sperm counts (TMSC) were significantly higher (P < 0.0001) in the group that achieved pregnancy. When the entire group was divided into “high” and “low” groups on the basis of the various parameters of semen analysis, the relative risk ratios for conception for the “high” groups were as follows: SC, 1.5; MOT, 8.5; TSC, 8.1; MSC, 5.8; and TMSC, 6.1. Life table analysis showed a statistically significant difference (P < 0.0001) in the initial rise and overall slope of the conception rates between the two groups for a number of the semen analysis parameters (TSC, MOT, MSC, and TMSC). This study showed that certain semen analysis parameters are positively correlated, with a high degree of statistical probability, with the time required for the occurrence of conception. The quantitative impact of the male fertility potential on conception rates was shown to correlate not solely with the SC or MOT values, but even more so with their derivatives (i.e., MSC and TMSC). Therefore, in an in vivo environment it is not only the number of sperm and their motility but also their derivatives that provide a quantitative insight into the male fertility potential. The data may provide a quantitative expression of the relative risk ratio for conception to occur and the time required until conception is achieved. Further studies will be necessary to clarify the effect of the other semen analysis parameters (i.e., morphology, velocity, linearity, and “efficient” MSC) on conception rates, cumulative conception rates, relative risk ratio for conception, and time until conception in a large population of infertile couples.
Suppressive Effects of Chronic Hyperprolactinemia on Penile Erection and Yawning Following Administration of Apomorphine to Pituitary‐Transplanted Rats
Authors: SATO FUMIO , AOKI HIKARU , NAKAMURA KAZUYOSHI , TAGUCHI MANABU , AOKI TOMOKO , YASUDA NAOKI
Published: October 2023

ABSTRACT: Recent studies showed in vivo and in vitro that acutely introduced prolactin (PRL) excess was capable of diminishing penile erectile function independently of the LH‐testosterone (T) dynamics. In the present investigation, we examined if such independent suppressive effects can be demonstrated in the pituitary‐transplant rat model with chronically elevated serum PRL. We also compared the effects of pituitary transplantation and castration on the level of erectile activity. Rats were made hyperprolactinemic by homologous transplantation of three anterior pituitaries underneath the kidney capsules, with the eutopic pituitaries left in situ. Before and 3,5, and 8 weeks after transplant or sham surgeries, 80 μg/kg s.c. injection of apomorphine was given as an inducer of erection. This was followed by 30‐minute observation periods during which the numbers of erections and yawning were recorded. Similar experiments were also performed with castrated rats without transplanted pituitaries. In the transplanted rats, plasma PRL was markedly elevated (51.4 ± 3.7 ng/ml) and was significantly (P < 0.001) higher than the values in the sham group (6.0 ± 2.7 ng/ml). In contrast, plasma T was not different (P > 0.05) between the two groups. The castrated rats showed very low plasma T (0.17 ± 0.01 ng/ml, P < 0.05 compared to the sham group) and normal PRL (P > 0.05). The numbers of both erection and yawning were significantly (P < 0.05 ∼0.01) less in the transplant than in the sham group 8 weeks after surgeries. Castrated rats showed a significant reduction (P < 0.05) only in the numbers of erection. These results indicated that the pituitary transplantation with chronic excess of PRL and castration with T deficiency caused roughly comparable degrees of suppression of penile erectile activity through mechanisms presumably independent from one another in the rat.
Evaluation of the Binding Patterns of Eleven FITC‐Conjugated Lectins in Fischer 344 Rat Testes
Authors: WINE ROBERT N. , CHAPIN ROBERT E.
Published: October 2023

ABSTRACT: The binding patterns of 11 recently commercially available fluorescein isothiocyanate‐conjugated lectins that have been uncharacterized or undercharacterized in rat testes and/or have an unknown or complex carbohydrate specificity were evaluated in paraffin sections from Fischer 344 rat testes. Several of the lectins exhibited unique binding patterns that provide information about changes in carbohydrate domains, particularly during germ‐cell maturation, that occur during spermatogenesis. Agaricus bisporus (ABA) lectin produced the most striking staining pattern in the cytoplasm of maturing germ cells, increasing in intensity until spermatid elongation, while the nuclei remained negative. In contrast, Cicer arietinum (CPA) strongly stained the nucleus of early leptotene/zygotene spermatocytes, decreasing to moderate intensity during maturation, until staining was irregular and scattered in elongated spermatids. This study describes new patterns of lectin staining during spermatogenesis and provides additional evidence of the complex carbohydrate modifications that occur as germ cells mature within the seminiferous tubule.
Hormone Treatment After Irradiation Stimulates Recovery of Rat Spermatogenesis From Surviving Spermatogonia
Authors: MEISTRICH MARVIN L. , KANGASNIEMI MARKO
Published: October 2023

ABSTRACT: The possibility of stimulating the recovery of spermatogenesis after irradiation using hormone treatment was tested in LBNF1 rats. At 10 weeks after irradiation with 3.5 Gy, the percentage of tubules showing recovery of spermatogenesis (repopulation index) was 37% in rats that received no hormone treatment. GnRH agonist (GnRH‐Ag) treatment with Zoladex or continuous treatment with testosterone markedly stimulated the recovery of spermatogenesis. When GnRH‐Ag treatment was started immediately after 3.5‐Gy irradiation and maintained for 10 weeks, the repopulation index was 91%. When an additional 6.5 weeks without further treatment was allowed between the 10‐week GnRH treatment and killing the rats, the repopulation index recovered to 100% and sperm counts to 83 × 106. These sperm counts were more than 100‐fold higher than those in rats not given hormone treatment and 50% of normal nonirradiated control levels. GnRH‐Ag for 10 weeks also stimulated spermatogenic recovery in rats irradiated with 6 Gy, even when the start of treatment was delayed until 18 weeks after irradiation. Without GnRH‐Ag, the repopulation index was 0, but in GnRH‐Ag‐treated rats it was 14.5%. Since all of the hormone treatments suppress intratesticular testosterone, high levels of testosterone may be inhibiting differentiation and their suppression may stimulate recovery. Even though the exact mechanism is not yet known, this method may still be applicable for clinical use to activate spermatogenesis in patients rendered azoospermic by irradiation or possibly by other cytotoxic treatments.
Androgen UDP‐Glucuronyl Transferase Activity Is Found Primarily in the Liver in the Human
Authors: PIROG EDYTA C. , COLLINS DELWOOD C.
Published: October 2023

ABSTRACT: In this study, androgen UDP‐glucuronyl transferase (UDPGT) activity was determined in microsomes of human liver, skin, and prostate. Androgen UDPGT activity was highest in the liver microsomes using 5α‐androstane‐3a, 17β‐diol (3αDIOL), androsterone (AN) and dihydrotestosterone (DHT) as substrates. The Km and Vmax values and enzyme velocity at the physiological concentration of the substrates in the liver microsomes were similar for AN and 3αDIOL The values for AN were as follows: Km = 16.9 μM, Vmax = 3.77 nmol/min/mg protein, and UDPGT velocity = 0.62 pmol/min/mg protein. The values for 3αDIOL were as follows: Km = 16.0 μM, Vmax = 5.61 nmol/min/mg protein, and UDPGT velocity = 0.42 pmol/min/mg protein. Androgen UDPGT activity was lower and showed less affinity for DHT (Km = 23.5 μM, Vmax = 0.84 nmol/min/mg protein, UDPGT velocity = 0.05 pmol/min/mg protein). No sex or age differences in 3αDIOL‐UDPGT activity were found in liver microsomes. The kinetic parameters and levels of androgen UDPGT activity in the skin and prostate samples were not determined because the levels of UDPGT activity were below the detection limit for our assay (0.003 pmol/min/mg protein). These results have important clinical implications. First, androgen UDPGT activity in the skin and prostate is much lower than the activity in the liver, suggesting that these tissues are not important sites for conjugation of androgens. Second, androgen UDPGT activity in the liver was not altered by sex or age in the 10 samples measured from men and women.
Discriminant Analysis Indicates a Single Sperm Protein (SP22) Is Predictive of Fertility Following Exposure to Epididymal Toxicants
Authors: KLINEFELTER G. R. , LASKEY J. W. , FERRELL J. , SUAREZ J. D. , ROBERTS N. L.
Published: October 2023

ABSTRACT: In a previous study, we found that ethane dimethanesulphonate (EDS) compromised the fertilizing ability of proximal cauda epididymal sperm from the rat within 4 days of exposure, an effect that persisted in castrated, testosterone (T)‐implanted animals, establishing direct action on the epididymis. This EDS‐induced reduction in fertilizing ability was highly correlated with a quantitative decrease in specific sperm protein. Here we sought to determine whether the fertility of proximal cauda epididymal sperm recovered from animals exposed to a variety of male reproductive toxicants could be predicted by assessing quantitative changes in specific sperm protein(s), or whether more common endpoints (e.g., sperm motility, sperm morphology, serum and epididymal tissue T, cauda epididymal sperm reserves) also are required to predict fertility. Intact adult male rats were dosed with EDS (25 or 50 mg/kg), chloroethylmethanesulphonate (CEMS; 12.5 or 18.75 mg/kg), or epichlorohydrin (EPI; 3 or 6 mg/kg) daily for 4 days. Castrated, T‐implanted rats were dosed with hydroxyflutamide (HFLUT; 12.5 or 25 mg/kg) daily for 5 days. On day 5, proximal cauda epididymal sperm were inseminated in utero into receptive, cervically stimulated adult females, and on day 9, fertility (implants/corpora lutea) was assessed. Fertility was decreased by the higher dose of each toxicant (P < 0.05) and also by the lower dose of EPI and HFLUT. Likewise, an acidic 22 kDa sperm protein (SP22) was decreased quantitatively (P < 0.05) in silver‐stained two‐dimensional gels by the higher dose of each toxicant as well as by the lower dose of EPI and HFLUT. Although sperm motility and serum T were altered by specific exposures, these endpoints were not useful in predicting fertility. In contrast, SP22 was highly correlated (P < 0.0001; r2 = 0.83) with fertility. Indeed, the amount of SP22 correctly predicted 90% and 94% of the fertile (>50% fertility) and subfertile (<50% fertility) animals, respectively, when discriminant analysis was performed. Thus, the amount of SP22 in a cauda epididymal sperm sample may be a useful predictor of fertility in toxicant‐treated animals.
Impaired Germ Cell Development in the Testes of Immature Rats With Neonatal Hypothyroidism
Authors: SIMORANGKIR DAVID R. , WREFORD NIGEL G. , de KRETSER DAVID M.
Published: October 2023

ABSTRACT: The induction of neonatal hypothyroidism from day 1 to day 25 postpartum using 6‐propyl‐2‐thiouracil (PTU) resulted in a 45% and 77% reduction of testis weight on days 20 and 30, respectively, and an increase in Sertoli cell number. The present study evaluated the effect of neonatal hypothyroidism on the developing germ cell population during the first 30 days postnatally. Qualitative and quantitative studies using the optical disector method were undertaken on the testes of control and hypothyroid rats, on days 10, 20, and 30 after birth. Germ cell development was obviously impaired in the hypothyroid rats, as shown by decreased primary spermatocyte and round spermatid numbers in day 20 and day 30 testes, and the persistence of gonocytes on days 10 and 20. These reductions obviously accounted for the reduced testis weight, absolute volume, and diameter of the seminiferous cords/tubules, especially on days 20 and 30. The failure to establish a seminiferous tubule lumen in hypothyroid rats probably reflects decreased fluid production and a functional immaturity of the Sertoli cells. The delay in germ cell maturation and increased degeneration may be because of the immature state of the Sertoli cell or result from the low follicle‐stimulating hormone and thyroxine levels known to occur in the hypothyroid rats.
Effects of Psychological Stress on Human Semen Quality
Authors: FENSTER LAURA , KATZ DAVID F. , WYROBEK ANDREW J. , PIEPER CARL , REMPEL DAVID M. , OMAN DOUGLAS , SWAN SHANNA H.
Published: October 2023

ABSTRACT: We investigated the relationship between psychological stress and sperm concentration, motility, and morphometry in a prospective study of 157 volunteers who were enrolled in a prepaid health plan. We measured psychological job stress and life‐event stress by telephone interview. Sperm‐kinematic and nuclear‐morphometric variables were measured using computer‐assisted image analyses. Sperm concentration, percent motility, and semen volume were determined by objective visual methods. We performed multiple linear regression for each semen variable to examine its relationship to stress, controlling for potential confounders. Stress at work and total number of life events were not related to differences in semen quality. However, the recent death of a close family member was associated with a reduction in straight‐line velocity (P = 0.002) and percent of progressively motile sperm (P = 0.02); it was also marginally associated with an increase in the fraction of sperm with larger and more tapered nuclei. These findings suggest that the fecundity of men experiencing the stress of a family member's death might be temporarily diminished.
Manidipine Improves Spermatogenesis in the Stroke‐Prone Spontaneously Hypertensive Rat
Authors: AKAGASHI KEIGO , KUMAMOTO YOSHIAKI , ITOH NAOKI , TSUKAMOTO TAIJI , SUZUKI TSUNEYUKI , OHTA YOSHIO
Published: October 2023

ABSTRACT: We evaluated the protective effects of manidipine, which is a long‐lasting calcium‐channel blocker, against damage to spermatogenesis arising from hypertensive vascular changes in stroke‐prone spontaneously hypertensive rats (SHRSP). SHRSP showed severe hypertension at 11 weeks of age, followed by hypertensive changes in intratesticular arterioles from 15 weeks of age. Manidipine lowered the blood pressure and the hypertensive vascular changes of intratesticular arterioles in SHRSP. The percentages of atrophic seminiferous tubules and tubules with less‐differentiated germ cells were increased in SHRSP at 23 weeks of age, although the administration of manidipine preserved spermatogenesis at a normal level. The transferrin concentration in testicular cytosol was comparable, whereas insulin‐like growth factor‐1 (IGF‐I) was reduced from 19 weeks of age in SHRSP. Manidipine preserved the normal IGF‐I concentration. Therefore, manidipine prevented the development of hypertensive vascular changes in the testis and maintained normal Sertoli cell function. As a result, manidipine protected spermatogenesis in SHRSP. These findings also suggested that hypertensive vascular changes in the testes play the most important role in spermatogenic damage in SHRSP.
Evidence for a Role of Intracellular‐Calcium Release in Nitric Oxide‐Stimulated Relaxation of the Rabbit Corpus Cavernosum
Authors: LEVIN ROBERT M. , HYPOLITE JOSEPH A. , BRODERICKT GREGORY A.
Published: October 2023

ABSTRACT: Erection is mediated by relaxation of the smooth muscle elements within the sinusoids of the corpus cavernosum. Although cavemosal relaxation can be mediated by a variety of mechanisms including purinergic stimulation, prostoglandins, and beta‐adrenergic stimulation the major mechanism involves the stimulated release of nitric oxide (NO) and subsequent relaxation of the corporal smooth muscle. Experimentally, NO can be released both by direct stimulation of NO‐containing nerves (using field stimulation) and indirectly via cholinergic stimulation of NO release from the endothelium (using bethanechol). Preliminary studies have indicated that NO release and/or NO‐stimulated relaxation of corporal smooth muscle is an active process involving both an increase in cytosolic calcium and an increase in metabolic energy utilization. Ryanodine is a pharmacological agent that can inhibit calcium‐stimulated calcium release from the sarcoplasmic reticulum. The results of the current study demonstrated that ryanodine inhibited both field‐stimulated relaxation and bethanechol‐stimulated relaxation but did not affect relaxation induced by adenosine triphosphate (ATP) or nitro‐prusside. These studies strongly support the hypothesis that NO‐stimulated relaxation is mediated, in part, by calcium release from the sarcoplasmic reticulum through ryanodine‐sensitive channels.