bluuebunny/crossref_metadata_2025 huggingface dataset:
Food Interaction and Steady‐State Pharmacokinetics of Itraconazole Oral Solution in Healthy Volunteers
Authors: Barone Joseph A. , Moskovitz Bruce L. , Guarnieri Joseph , Hassell Alan E. , Colaizzi John L. , Bierman Robert H. , Jessen Lois
Published: October 2023

Study Objectives. To evaluate the effect of food on the bioavailability of itraconazole (ITR) hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) solution under multiple‐dose to steady‐state conditions, and to determine the pharmacokinetics of ITR solution at steady state.

Design. Open‐label, randomized, multiple‐dose, crossover study.

Setting. University‐affiliated health center.

Patients. Thirty healthy men randomized to one of two treatment sequences (fasted‐fed, fed‐fasted).

Interventions. Subjects were either fasted or fed a standard breakfast before receiving ITR oral solution 200 mg once/day for 15 days. Crossover phases were separated by a 4‐week washout period.

Measurements and Main Results. On day 1, blood samples were collected before the dose (time zero) and 0.5, 1, 2, 3, 4, 5, 6, 8, 12, and 24 hours after the dose. Trough samples were obtained before the dose on days 4, 7, 12, 13, and 14. On day 15, samples were obtained at the same times as day 1, and at 36, 48, 72, 96, 168, 240, and 360 hours. Samples were analyzed by high‐performance liquid chromatography for ITR and its major metabolite hydroxyitraconazole (OH‐ITR). Urine was collected on days 1 and 15 before and 0–8 and 8–24 hours after the dose; HP‐β‐CD was measured by size‐exclusion chromatography. Mean bioavailabilities of ITR and OH‐ITR were 43% and 38% higher, respectively, when ITR solution was taken as a single dose under fasted conditions. With multiple dosing, steady state was achieved by day 14. At steady state, mean bioavailabilities were 29% and 17% higher, respectively, in the fasted state; terminal half‐life was similar under fasted and fed conditions (mean 39.8 and 37.5 hrs for ITR, respectively; 27.3 and 26.2 hrs for OH‐ITR, respectively). HP‐β‐CD was eliminated almost exclusively in urine.

Conclusion. The bioavailability of ITR and OH‐ITR is enhanced when ITR oral solution is given in the fasted state; this was true for both single and multiple dosing to steady state.
Fatal Toxic Epidermal Necrolysis Related to Lamotrigine Administration
Authors: Page Robert Lee , O'Neil Michael G. , Yarbrough Dabney Randolph , Conradi Sandra
Published: October 2023

Toxic epidermal necrolysis (TEN) and Stevens‐Johnson syndrome (SJS) are severe life‐threatening dermatologic conditions. To date, eight cases of TEN and one of SJS related to lamotrigine administration have been reported in the literature. Most patients were also taking concomitant valproic acid. It was hypothesized that valproic acid may interfere with glucuronidation of lamotrigine, leading to increased serum lamotrigine levels, or perhaps alter the drug's metabolism, resulting in accumulation of a toxic intermediate metabolite. Ultimately, this may possibly predispose a patient to increased dermatologic reactions, including TEN. A 54‐year‐old man developed TEN 4 weeks after beginning lamotrigine for complex partial seizures related to a glioblastoma multiforme brain tumor. The patient had also been taking concomitant allopurinol and captopril for more than 4 years with no complications, and valproic acid 3 months before the cutaneous event. Despite aggressive intensive care management, the patient died 17 days from the onset of symptoms due to multiple organ failure. Administration of lamotrigine, especially in combination with valproic acid, may lead to the development of TEN.
Subcutaneous Enoxaparin for Outpatient Anticoagulation Therapy in a Patient with an Aortic Valve Replacement
Authors: Manley Harold J. , Smith Judith A. , Garris Robert E.
Published: October 2023

Low‐molecular‐weight heparins have been administered for a variety of clinical conditions. A patient with a mechanical aortic valve replacement patient underwent elective transurethral prostatectomy. Anticoagulation was managed with unfractionated heparin immediately preoperatively and postoperatively. Warfarin was begun on postoperative day 1. The patient had a prolonged hospitalization due to subtherapeutic international normalized ratios (INR) despite warfarin administration. Because he intended to leave the hospital against medical advice before therapeutic INR was achieved, enoxaparin 1 mg/kg subcutaneously every 12 hours was prescribed to provide anticoagulation, facilitating discharge and improving the patient's quality of life. Enoxaparin was associated with an approximate saving of $4500 over warfarin. The only adverse event reported was bruising at the injection site.
The Stroke Therapy Research Boom: Implications for the Hospital Formulary
Authors: Bender N. Kathryn
Published: October 2023

Research into drug therapy for the acute treatment of ischemic stroke is now booming, and a number of promising drugs with very different mechanisms of action are at an advanced stage of development. Ideally, use of single agents or combinations of agents will result in favorable neurologic and functional outcomes for the majority of stroke patients. Given the current focus within our society on controlling health care costs, pharmacoeconomic tools will be important in determining which of these agents should achieve formulary acceptance. Cost‐minimization analysis, cost‐benefit analysis, cost‐effectiveness analysis, and cost‐utility analysis are all likely to be valuable methodologies to aid in decision making. More complex situations may require the use of decision‐tree analysis.
TIMI Grade Flow, Mortality, and the GUSTO‐III Trial
Authors: Stringer Kathleen A.
Published: October 2023

Thrombolytic therapy dates back to animal studies performed in the early 1940s, although clinical trials did not begin until the early 1980s. Many large, placebo‐controlled trials conclusively recorded improved survival with thrombolytics in the treatment of acute myocardial infarction. However, only recently did clinical trials compare tissue plasminogen activator (tPA) and streptokinase (SK), and only one study showed a difference in mortality between them. This discrepancy, in part, led to the open‐artery hypothesis that early and sustained infarct‐related artery patency improves outcome. This theory was tested in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO‐I) study. The angiographic substudy of GUSTO‐I provided strong evidence for the relationship between 90‐minute thrombolysis in myocardial infarction (TIMI) grade 3 flow and lower mortality. However, despite significantly higher 90‐minute TIMI grade 3 flow (54% vs 32%) with accelerated tPA versus SK plus intravenous heparin, the absolute difference in mortality rate was less than 1%. The recently completed GUSTO‐III trial compared accelerated tPA with reteplase (rPA). Based on the open‐artery hypothesis and previous data showing an absolute difference of 15% in 90‐minute TIMI grade 3 flow between the agents, it was anticipated that mortality would be lower with rPA than with accelerated tPA. The GUSTO‐III study showed no significant difference in 30‐day mortality for the agents (7.47% vs 7.24%, p=0.61), respectively. These results raise questions about the validity of the hypothesis: if 90‐minute TIMI grade 3 flow is such a strong predictor of mortality, why is there not a greater difference in mortality rates for thrombolytic agents?
The Role of Endothelin in Heart Failure and Hypertension
Authors: Nguyen B. Nhi T. , Johnson Julie A.
Published: October 2023

The endothelin family consists of three structurally similar isopeptides: ET‐1, ET‐2, and ET‐3. The two receptor subtypes, ETA and ETB, have‐different receptor affinities for the isopeptides. Stimulation of ETA and ETB receptors results in vasoconstriction, and ETB stimulation also causes vasodilation. These receptors may have profound impact on the etiologies of various diseases, including heart failure and hypertension. Studies with endothelin‐receptor antagonists in animals and humans with heart failure show promising short‐ and long‐term results. The place of the agents in the treatment of essential hypertension remains controversial, but they may have a greater role in hypertensive blacks and transplant recipients.
Tramadol‐Warfarin Interaction
Authors: Sabbe Jonell R. , Sims Pamela J. , Sims Marion H.
Published: October 2023

A 61‐year‐old women receiving warfarin after mitral valve replacement experienced extensive ecchymoses after starting tramadol therapy. Laboratory values revealed critical elevations of prothrombin time and international normalized ratio. The patient's coagulation values returned to acceptable levels after discontinuing tramadol and temporarily stopping warfarin. The mechanism for this interaction is unknown. Practitioners should be aware of the possibility of such a interaction and exercise caution when tramadol is prescribed for a patient receiving warfarin.
Effect of Blood Glucose Concentrations on the Development of Chronic Complications of Diabetes Mellitus
Authors: Swidan Sahar Z. , Montgomery Patricia A.
Published: October 2023

Diabetes is associated with increased risk of cardiovascular disease, coronary heart disease, stroke, acute myocardial infarction, blindness, and renal failure. Strategies to reduce their occurrence are an essential focus of patient care. More than one pathogenic process is involved, and genetics influence the risk. Hyperglycemia is a factor in the development of microvascular and possibly macrovascular complications. Two possible mechanisms of glucose damage are glycation of proteins and the polyol pathway. Research led to the identification of drugs that block parts of the pathways. In clinical trials, intensive control of blood glucose concentrations decreased the risk of microvascular complications. Adverse effects associated with intensive therapy, however, include hypoglycemia and weight gain.
The Role of Troglitazone in Treating the Insulin Resistance Syndrome
Authors: Granberry Mark C. , Schneider Eric F. , Fonseca Vivian A.
Published: October 2023

Insulin resistance is characterized by impaired responsiveness to endogenous or exogenous insulin and often results in the insulin resistance syndrome, a clustering of cardiovascular risk factors that includes abdominal obesity, hypertension, dyslipidemia, glucose intolerance, and hyperinsulinemia. Although the mechanism responsible for insulin resistance has not been completely defined, it is likely due to defective insulin receptor signaling and results in decreased use of glucose. Troglitazone, the first in a new class of drugs, directly decreases insulin resistance by improving insulin‐mediated glucose disposal and reduces plasma insulin concentrations. Glycemic control achieved with troglitazone monotherapy is equivalent to that with sulfonylurea and metformin, and when combined with these agents offers additional plasma glucose reduction. Studies are necessary to determine the effect of thiazolidinediones on morbidity and mortality of patients with type 2 diabetes and insulin resistance.
Chest Discomfort Associated with Liposomal Amphotericin B: Report of Three Cases and Review of the Literature
Authors: Johnson Melissa D. , Drew Richard H. , Perfect John R.
Published: October 2023

Liposomal formulations of amphotericin B are designed to maintain therapeutic efficacy of amphotericin B deoxycholate while reducing its associated toxicities. In three patients chest discomfort occurred during planned 1‐hour infusions of liposomal amphotericin B (AmBisome) 3 mg/kg/day during an open‐label trial. The first patient experienced chest tightness and difficulty breathing and the second had dyspnea and acute hypoxia, both within 10 minutes of the start of the infusion. The third patient complained of chest pain 5 minutes after the start of two infusions. All symptoms resolved on terminating therapy. Two patients were later rechallenged with slower infusions and tolerated the drug well. A review of the English‐language literature revealed only two other case reports of infusion‐related chest or pulmonary reactions with the drug, although similar reactions were noted in several reports of clinical trials. Further review of the literature revealed reports of chest and pulmonary adverse events with other liposomal formulations of amphotericin B, liposomal daunorubicin, liposomal doxorubicin, and liposomes. The pathophysiology of such reactions remains unclear, and premedication with diphenhydramine did not completely prevent this reaction in one of our patients. We recommend infusing liposomal amphotericin B over at least 2 hours with careful monitoring for adverse reactions.
Clinical Pharmacy Services in Hospitals Educating Pharmacy Students
Authors: Raehl Cynthia L. , Bond C. A. , Pitterle Michael E.
Published: October 2023

In 1995 we conducted a national survey of 1102 acute care hospitals in the United States to determine types of clinical pharmacy services, patient‐focused care, and pharmaceutical care used to educate and train pharmacy students, and compared outcomes with surveys in 1989 and 1992. Clinical pharmacy services offered in 50% or more of Pharm.D.‐affiliated hospitals (core services) were drug‐use evaluation, in‐service education, pharmacokinetic consultations, adverse drug reaction management, drug therapy monitoring, protocol management (most common for aminoglycosides, nutrition, antibiotics, heparin, warfarin, theophylline), nutrition team, and drug counseling. Comprehensive pharmaceutical care programs were established in 64%, 42%, and 33% of Pharm.D., B.S., and nonteaching hospitals, respectively. Patient‐focused care programs were beginning or established in 77%, 71%, and 60%, respectively. Pharmacists served as care team leaders in 23% of hospitals affiliated with a college of pharmacy. Most common ambulatory care clinics were oncology, anticoagulation, diabetes, geriatrics, refill, and infectious diseases/HIV. For‐profit hospitals rarely provided education for pharmacy students. Thus patient‐focused and comprehensive pharmaceutical care programs exist according to a hospital's academic program affiliation with Pharm.D. or B.S. degree program.
Oral Amiodarone: Historical Overview and Development
Authors: Pollak P. Timothy
Published: October 2023

Objectives. To review the historical development of amiodarone and the changing perceptions of the drug, and discuss its electrophysiologic, pharmacologic, and pharmacokinetic properties.

Methods. Review of relevant literature.

Results. In the 1970s and 1980s a plethora of new antiarrhythmic agents, including amiodarone, was introduced. Amiodarone is predominately a class III antiarrhythmic, but also possesses class I, II, and IV effects. By 1977 it was described as the ideal antiarrhythmic agent. However, clinicians underestimated potential difficulties caused by misunderstanding its variable absorption, slow initial response at nonloading dosages, and extended half‐life. Elevated dosages also produced frequent adverse effects. Thus, early enthusiasm for the drug's efficacy was gradually replaced by a focus on its toxicity. The 1990s witnessed reacceptance of the agent as more logical initial regimens and lower maintenance dosages decreased adverse effects, and amiodarone emerged as one of the few drugs effective in suppressing and preventing arrhythmias that does not increase mortality. Remaining challenges include delineation of an optimal oral regimen, identification of markers useful in clinical monitoring, and elucidation of the relationship between dose‐tissue concentration and response and dose‐toxicity associations.

Conclusion. Amiodarone is an increasingly valuable component of today's antiarrhythmic therapy.
Rationale, Development, and Clinical Outcomes of a Multidisciplinary Amiodarone Clinic
Authors: Sanoski Cynthia A. , Schoen Marieke D. , Gonzalez Rose C. , Avitall Boaz , Bauman Jerry L.
Published: October 2023

Objectives. To review the rationale and development of a multidisciplinary amiodarone clinic, and document the clinical outcomes resulting from its implementation.

Methods. A clinic was established to provide an ambulatory setting in which patients receiving amiodarone could be followed according to published guidelines by a multidisciplinary team of cardiovascular health care specialists. Patients receiving amiodarone were referred to the clinic by their primary physicians. A data base containing each patient's medical history, current drug therapy, and baseline laboratory values was developed during the initial visit. Liver function tests, thyroid function tests, and chest radiographs were performed every 6 months, and pulmonary function tests were scheduled on an annual basis. Dosage adjustments were performed in select patients.

Results. Since November 1996, 60 patients have been referred to the amiodarone clinic. Mean length of follow‐up before and after referral was 16.3 ± 25.5 and 9.2 ± 5.5 months, respectively. Laboratory tests were performed according to accepted guidelines in 14 (23%) patients before referral compared with 54 (90%) patients after enrollment (p<0.001). Previously unrecognized adverse events were detected in 21 (35%) patients, including pulmonary fibrosis, QT prolongation, liver enzyme elevation, hypothyroidism, hyperthyroidism, and asthma exacerbation. Amiodarone was discontinued in six patients, four of whom had suspected pulmonary toxicity. The dose of amiodarone was adjusted in 29 (48.4%) patients.

Conclusion. Many patients receiving amiodarone are not being followed according to published recommendations. Implementation of a specialized, multidisciplinary amiodarone clinic improves outcomes by monitoring for early detection of drug‐related toxicities and by facilitating proper dosage modifications.
Activation of Coagulation Factor×in Human Semen
Authors: CARSON STEVEN D. , de JONGE CHRISTOPHER J.
Published: October 2023

ABSTRACT: Tissue factor (TF) is an essential cofactor for factor VII (fVII) in initiating blood coagulation. Recently, TF was shown to be present in human semen and to be associated with prostasomes that originate from prostatic secretions. In the blood coagulation cascade, the complex of TF and activated factor VII (fVIIa) can activate both factor×and factor IX, by limited proteolysis. In the present study, we investigated the ability of semen to activate factor X. We also determined that factor×was activated predominantly by TF‐fVIIa and that most of the TF was present in the seminal plasma, consistent with prostasome localization. No endogenous factor×was detected in semen, but activation of added factor×occurred in the absence of added fVIIa. Subsequent experiments showed that seminal plasma contains endogenous fVII‐like activity, but the addition of more fVIIa increased factor×activation. Thus, while seminal plasma contains significant amounts of TF, its potential to activate factor×is limited by fVII availability and by the absence of endogenous factor X. Evaluation of semen specimens from infertility patients revealed a 16‐fold variation in TF‐fVII activity. No relationship between TF and number of days of abstinence, specimen pH, sperm count, or sperm motility was evident. Additional factor X‐activating potential, independent of further TF activity, was generated in seminal plasma after treatment of semen with calcium and ionophore A23187. Production of this additional activity was blocked by the addition of anti‐TF antibody during the activation. Since there is no factor×endogenous to semen, the additional activity stimulated by A23187 appears to be due to an endogenous, non‐factor×substrate for TF‐fVII in semen. This endogenous substrate may be either factor IX or a novel new substrate for TF‐fVIIa. Future experiments will test these hypotheses.
Presence and Modulation of Interleukin‐12 in Seminal Plasma of Fertile and Infertile Men
Authors: NAZ RAJESH K. , EVANS LORI
Published: October 2023

ABSTRACT: Interleukin‐12 (IL‐12) is a unique cytokine that recently has drawn considerable attention because of its immunomodulatory properties and its possible involvement in several normal physiological and pathophysiological processes. In the present study, concentrations of IL‐12 were determined, in the seminal plasma of fertile (n = 33), male‐factor—infertile (n = 27), and immunoinfertile (n = 14) men, to investigate its role, if any, in male infertility. Levels of IL‐12 were expressed both as picograms per milliliter and as programs per milligram protein. IL‐12 was detected in seminal plasma of fertile men as well as in that of infertile men. The levels of IL‐12 in seminal plasma of both male‐factor and immunoinfertile men were significantly (P < 0.05) different from those of fertile men, when levels were expressed as picograms per milligram protein. When expressed as picograms per milliliter, the levels of IL‐12 differed significantly between the immunoinfertile group and the fertile/malefactor—infertile group. There was significant correlation between the IL‐12 levels and the total sperm count and percentage of morphologically normal sperm in the semen, whether groups were analyzed together or individually by condition. These findings suggest that IL‐12 may have a role in fertility and that its derangement may be involved in male infertility.
Detection of Human Glandular Kallikrein, hK2, as Its Precursor Form and in Complex With Protease Inhibitors in Prostate Carcinoma Serum
Authors: GRAUER LANA S. , FINLAY JUDITH A. , MIKOLAJCZYK STEPHEN D. , PUSATERI KELLIE D. , WOLFERT ROBERT L.
Published: October 2023

ABSTRACT: Forms of human glandular kallikrein (kK2) in prostate carcinoma serum were identified using monoclonal antibodies specific for hK2 and prohK2. Recombinant mammalian hK2, prohK2, and prostate = specific antigen (PSA) were utilized to confirm the specificity of monoclonal antibodies for hK2 and the lack of reactivity with PSA. In prostate cancer patient sera containing high levels of hK2 (>100 ng/ml), hK2 exists as a complex with α1‐antichymotrypsin with a molecular weight of 90 kDa. The kallikrein also exists as a 32‐kDa free form, which includes the precursor pro form of hK2. The relative amount of complex and free hK2 varied, but in most sera examined the 32‐kDa form predominated. Recombinant hK2 readily formed complexes with α2‐macroglobulin when the two proteins were incubated together as well as when hK2 was spiked into female serum.
Antioxidant Potential of Human Serum Albumin: Role in the Recovery of High Quality Human Spermatozoa for Assisted Reproductive Technology
Authors: ARMSTRONG JEFFREY S. , RAJASEKARAN MAHADEVAN , HELLSTROM WAYNE J. , SIKKA SURESH C.
Published: October 2023

ABSTRACT: Human serum albumin (HSA) is being considered as an alternate media for sperm enrichment in assisted reproductive technology (ART) because of recent concern with the use of Percoll. In this study, we compared HSA and Percoll for 1) sperm recovery, 2) reactive oxygen species scavenging potential, and 3) effects on total oxidative stress to spermatozoa. The spermatozoa‐enriched fractions obtained from Percoll (80%:40%) and HSA (12%) were monitored for sperm motility, viability, hypoosmotic swelling test (HOST), and adenosine triphosphate (ATP) levels. The effect of superoxide anions (O2−) on donor human spermatozoa was observed in the presence of either HSA or Percoll media. A combination of luminol and the Cypridina luciferin analog 2‐methyl‐6‐(4‐methoxyphenyl)‐3,7‐dihydroimidazo(1,2‐α)pyrazin‐3‐one hydrochloride was used as a highly sensitive chemiluminescence probe in our hypoxanthine and xanthine oxidase‐based assay for O2−. Sperm membrane total oxidative stress was determined by measuring levels of the prostanoid 8‐iso‐Prostaglandin F2 (8‐iso‐PGF2). Significant differences in sperm parameters between the Percoll‐enriched spermatozoa (motility 60% ± 4%, viability 56% ± 6%, and HOST 73% ± 7%) and those enriched with HSA (motility 84% ± 5%, viability 85% ± 4%, and HOST 84% ± 3%; P < 0.01) were observed. Adenosine triphosphate levels were significantly higher, by almost 50%, in samples processed with HSA than with Percoll (P = 0.03). The dismutation rate of O2− in HSA (slope −6.8) was significantly lower than in Percoll (slope −87.0; P < 0.01). Sperm motility and ATP levels decreased at a slower rate after treatment with O2− in the presence of HSA when compared to Percoll; moreover, spermatozoa in HSA regained partial motility after 2 hours, whereas spermatozoa in Percoll were immobilized. No significant differences in 8‐iso‐PGF2 levels in spermatozoa enriched by either HSA or Percoll were observed. We conclude that the HSA sperm enrichment procedure improves the recovery of higher quality spermatozoa compared to Percoll and, because of its antioxidant properties, may be useful in processing high leukospermia semen samples for ART purposes.
FSH Does Not Directly Influence Testicular Macrophages
Authors: CARPENTER ANNE M. , LUKYANENKO YEVGENIYA O. , LEE VAUGHAN H. , HUTSON JAMES C.
Published: October 2023

ABSTRACT: We have previously demonstrated that conditioned medium from testicular macrophages stimulates testosterone production by Leydig cells. It was also reported that conditioned medium from macrophages treated with follicle‐stimulating hormone (FSH) had an even greater amount of Leydig cell—stimulating activity than medium from untreated macrophages, indicating that this factor is under the regulation of FSH. However, most other laboratories have been unable to reproduce this effect of FSH. We have recently purified and partially characterized the stimulatory factor from macrophage‐conditioned medium that stimulates Leydig cells. The purpose of the present investigation was to reinvestigate the effect of FSH by determining whether it regulates the production of this purified factor and by determining whether macrophages have mRNA for the FSH receptor. Testicular macrophages were isolated from adult rats and incubated 24 hours with human recombinant FSH (20 units/ml), ovine FSH (200 ng/ml), fetal bovine serum (2%), or dibutyryl cyclic adenosine monophosphate (1 mM). The macrophage‐derived factor (MDF) was then purified from conditioned medium of the various treatment groups and added to Leydig cells. The concentration of testosterone in the Leydig cell medium was then measured after 16 hours. It was found that serum significantly stimulated production of the MDF. However, FSH had no effect on production of the MDF in the presence or absence of serum. Dibutyryl cyclic adenosine monophosphate exerted a slight inhibitory effect on production of the macrophage‐derived factor. Most importantly, testicular macrophages did not express detectable levels of FSH receptor mRNA, either in vivo or in vitro, when evaluated using either in situ hybridization or northern analysis, under identical conditions that clearly demonstrated FSH receptor mRNA in Sertoli cells. We conclude that testicular macrophages are not a direct target for FSH.
Interaction Between Ca2+, Cyclic 3‘,5’ Adenosine Monophosphate, the Superoxide Anion, and Tyrosine Phosphorylation Pathways in the Regulation of Human Sperm Capacitation
Authors: LECLERC PIERRE , de LAMIRANDE EVE , GAGNON CLAUDE
Published: October 2023

ABSTRACT: In order to fertilize the egg, spermatozoa must go through the capacitation process where they experience Ca2+ uptake, increases In cyclic 3′,5′ adenosine monophosphate (cAMP) concentrations, superoxide anion production, and protein tyrosine phosphorylation. Although the importance of these processes has been described, the interactions between them, as well as the temporal sequence of these events, remain to be demonstrated. Previous studies from our laboratory have demonstrated that tyrosine phosphorylation of p105 and p81 (p105/81), the two major human sperm phosphoty‐rosine‐containing proteins, was under cAMP and oxygen derivatives regulation. In the present study, we investigated the importance of intra‐ and extracellular Ca2+, as well as the phosphodiesterase inhibitor 3‐isobutyl‐1‐methytxanthine and the phosphatase inhibitors calyculin A and okadaic acid, in the production of superoxide anion and p105/81 tyrosine phosphorylation. An increase in p105/81 phosphotyrosine content was observed when spermatozoa were incubated in the absence of extracellular Ca2+ or with the calmodulin antagonist N‐(6‐aminohexyl)‐1‐naphthalenesulfonamide. However, the human sperm capacitation inducer FCSu (ultrafiltrate of fetal cord serum) requires the presence of the extracellular Ca2+ to induce capacitation, superoxide anion production, and tyrosine phosphorylation of p105/81, whereas free intracellular Ca2+ had no effect on these last two processes. The production of superoxide anion by spermatozoa was stimulated by inhibitors of phosphodiesterases and serine/threonine phosphoprotein phosphatases. The tyrosine phosphatase inhibitor vanadate decreased by 40% the FCSu‐stimulated superoxide anion production, although it had no effect when used alone. These results suggest that, during sperm capacitation, Ca2+ induces an elevation in cAMP levels; this cAMP, through undefined serine/threonine protein phosphorylation, stimulates the generation of superoxide anion, which, in turn, causes the increase in p105/81 phosphotyrosine contents.
Patterns of Efferent Lymphatics of the Mouse Testis
Authors: ITOH MASAHIRO , LI XIU‐QIN , YANO AKIKO , XIE QIANG , TAKEUCHI YOSHIKI
Published: October 2023

ABSTRACT: Previous studies in the rat demonstrated that lymph vessels arise from various sites in the testis and then anastomose to form the main lymph trunk toward the testicular artery. Although mice are as commonly used in the laboratory as the rat, precise knowledge concerning their testicular lymphatics has not been established. In the present study, the patterns of testicular lymphatic drainage in the mouse were examined using local injection of India ink into the testicular parenchyma. The results demonstrated that, besides the lymph trunk surrounding the testicular artery, a lymphatic drainage route running along the ductus deferens is also present.
Müllerian Inhibiting Substance Improves Longevity of Motility and Viability of Fresh and Cryopreserved Sperm
Authors: SIOW YONG , FALLAT MARY E. , AMIN FALGUNI A. , BELKER ARNOLD M.
Published: October 2023

ABSTRACT: Müllerian inhibiting substance (MIS) is a hormone present in seminal plasma, but its role is unknown. In this study, the effects of MIS on sperm survival in fresh and cryopreserved specimens were investigated. Fresh sperm motility and viability (n = 12) were evaluated in specimens after 0, 0.5, 1, 3, 5, and 22 hours of incubation in the presence or absence of MIS. Motile and nonmotile sperm were evaluated in Cell‐Vu counting microscope slides, and viability was assessed by eosin‐nigrosin exclusion. Sperm cryopreserved for 2 weeks in TES (N‐Tris[hydroxymethyl]methyl‐2‐aminoethanesulfonic acid)‐Tris‐glycerol‐egg yolk buffer and 4% glycerol with or without MIS were thawed at room temperature (n = 6) and were evaluated for motility and viability using identical methods to those used with fresh sperm. The effects of MIS were examined by coincubation with monoclonal anti‐MIS antibody (6E11; n = 6). In fresh and cryopreserved sperm incubated with MIS, both motility and viability were higher than in the absence of MIS (P < 0.03; Wilcoxon signed rank test) at 5 and 22 hours. Coincubation with anti‐MIS antibody eliminated the effects of MIS. Longevity of sperm motility and viability are improved both in fresh and cryopreserved sperm in the presence of MIS and may have potential for use in assisted reproductive technology.
Development of Sertoli Cell Binding Competency in the Peripubertal Rat
Authors: CAMERON DON E , MUFFLY KARL E. , NAZIAN STANLEY J.
Published: October 2023

ABSTRACT: The peripheral distribution of Sertoli cell F‐actin, a cytoskeletal protein found in Sertoli cell ectoplasmic specializations, is associated with enhanced spermatid binding to the Sertoli cell and, as such, serves as a functional marker for its acquisition of binding competency. Previous studies suggest that the peripheral distribution of actin is dependent on follicle‐stimulating hormone (FSH). To investigate the developmental pattern of Sertoli cell actin distribution in relation to peripubertal FSH and testosterone levels, we examined epithelial sheets from 2–8 week‐old‐rats. Tissues were processed for light microscopy and for the visualization of rhoda‐mine‐labeled F‐actin. At 2 weeks, actin staining was diffuse throughout most of the Sertoli cells and was similar to that observed in binding‐incompetent Sertoli cells. By 4 weeks, actin distribution was peripheral, acquiring the same staining pattern as observed in binding‐competent Sertoli cells. Serum levels of FSH peaked at 4 weeks and declined to adult levels thereafter. Testosterone levels did not increase significantly until 6 weeks. Results show that Sertoli cell actin undergoes peripheral reorganization concurrent with the peripubertal peak of FSH but prior to the peripubertal rise of testosterone. The study demonstrates a temporal correlation between the peripubertal FSH rise and the actin redistribution in Sertoli cells that is consistent with an induction of this redistribution by FSH. These results suggest that FSH induces binding competency in Sertoli cells.
Characterization of a TPA‐Response Element in the 5‘‐Flanking Region of the Androgen Receptor Gene
Authors: KUMAR M. VUAY , JONES EVAN A. , FELTS SARA J. , BLEXRUD MARCEIL D. , GROSSMANN MICHAEL E. , BLOK LEEN J. , SCHMIDT LUCY J. , TINDALL DONALD J.
Published: October 2023

ABSTRACT: The androgen receptor (AR) protein is an important transacting factor that is necessary for mediating gene expression of androgen‐responsive genes. The expression of the AR gene is regulated by androgens and agents that utilize the calcium, protein kinase A, and protein kinase C pathways. Although the role of the calcium and protein kinase A pathways in the regulation of the AR gene has been investigated, the mechanism of regulation of AR through the protein kinase C pathway is not known. We have isolated the 5′‐flanking region of the mouse AR gene and identified a consensus TPA (12‐O‐tetradecanoylphorbol 13‐acetate)‐responsee lement (TRE). Transient transfection assays indicate that the TRE sequence is sufficient to confer TPA responsiveness to cells treated with TPA. Gel retardation assays and DNA footprint analysis demonstrated specific binding of the TRE and protection of the TRE sequence. Thus, these results describe a TRE in the 5′‐flanking region of the AR gene and demonstrate that the TRE is responsive to TPA treatment.
Characterization of Cysteamine as a Potential Contraceptive Anti‐HIV Agent
Authors: ANDERSON ROBERT A. , FEATHERGILL KENNETH , KIRKPATRICK RISA , ZANEVELD LOURENS J. D. , COLEMAN KEVIN T. , SPEAR PATRICIA G. , COOPER MORRIS D. , WALLER DONALD P. , THOENE JESS G.
Published: October 2023

ABSTRACT: Cysteamine (β‐mercaptoethylamine, or MEA) is a thiol‐reducing agent and has anti‐HIV activity. Because of these properties, cysteamine was evaluated as a vaginal contraceptive and tested for its effects on sperm function and on other sexually transmitted microbes. Cysteamine was contraceptive in the rabbit. Conception was inhibited completely when sperm were pretreated with 500 μg/ml cysteamine and was inhibited by more than 60% when 7.5 mg cysteamine was applied vaginally as a suspension in 50% K‐Y Jelly. Cysteamine had multiple effects on spermatozoa. Both acrosin (EC 3.4.21.10) and hyaluronidase (EC 3.2.1.35) were reversibly inhibited by cysteamine. Calculated IC50 values were 370 μg/ml and 150 μg/ml for acrosin and hyaluronidase, respectively. Cysteamine behaved as a poor spermicide when activity was measured by the 30‐second Sander‐Cramer test. However, sperm motility was inhibited completely when cysteamine was preincubated for 10 minutes prior to motility evaluation, at concentrations as low as 50 μg/ml. The calcium bnophore A23187—induced human acro‐some reaction was inhibited by cysteamine (IC50 = 0.5 μg/ml). Neither herpes simplex virus nor Neisseria gonorrhoeae was affected by cysteamine at concentrations as high as 500 μg/ml and 100 μg/ml, respectively. Cysteamine appears to have no effect on normal vaginal flora (i.e., lactobacillus). These results, together with published data, strongly support the further development of cysteamine as a topical contraceptive anti‐HIV agent.
Evidence for Nitric Oxide Regulation of Hamster Sperm Hyperactivation
Authors: YEOMAN RICHARD R. , JONES WILLIAM D. , RIZK BOTROS M.
Published: October 2023

ABSTRACT: Involvement of reactive oxygen species has been implicated in the process of hyperactivation and capacitation of sperm. Nitric oxide has recently been found to function both as an intracellular and extracellular messenger, with its synthetic enzyme found in several cell types, including male and female genital tract organs. The objective of the present study was to investigate the role of nitric oxide in hamster sperm hyperactivation. Caudal epididymal contents of mature golden hamster sperm were diluted with human tubal medium supplemented with a sperm motility preparation. Inhibitors of nitric oxide synthase (nitro‐l‐arginine, methyl‐l‐arginine, and 1,3‐phenylene‐bis[1,2‐ethenediyl]‐bis‐isothiourea) were added to incubation media in various doses. Alternatively, a nitric oxide donor, sodium nitroprusside, was used. The percentage motile and grade of movement were recorded at intervals encompassing the normal period of capacitation and hyperactivation. Acrosomal status was evaluated by phase contrast microscopy. Inhibition of nitric oxide synthesis did not affect motility during early capacitation but dramatically inhibited later hyperactivation. An inactive stareo‐enantomere of the inhibiting drug had no effect. Addition of nitric oxide to nonstimulated sperm induced hyperactivation in a similar time course. In conclusion, nitric oxide plays a significant role in hyperactivation of hamster epididymal sperm.
Suppression and Recovery of Spermatogenesis Following Spinal Cord Injury in the Rat
Authors: HUANG H. F. S. , LINSENMEYER T. A. , ANESETTI R. , GIGLIO W. , OTTENWELLER J. E. , POGACH L.
Published: October 2023

ABSTRACT: Recently, we reported that changes in spermatogenesis in adult rats during acute phase (within 2 weeks) of spinal cord injury (SCI) were associated with a suppression of pituitary‐testis hormone axis, and these effects mimic those that occur after hormone deprivation. In this study, we examined the long‐term (>4 weeks) effects of SCI on spermatogenesis and its recovery. Results of this study reveal that while serum follicle stimulating hormone, luteinizing hormone, and testosterone levels in SCI rats recovered within 1 month after the injury, their spermatogenesis continued to regress. By 3 months, spermatogenesis in 70% of SCI rats has totally regressed, characterized by the absence of proliferating spermatogonia; these effects could not be prevented by an otherwise effective regimen of testosterone treatment. Sertoli cells in the regressed seminiferous tubules exhibited unusual behavior, characterized by the formation of multiple cell layers and/or aggregates that extended into the tubular lumen. Active spermatogenesis was observed in nine of the 19 SCI rats by 6 months, seven of which had complete spermatogenesis, but with persisting abnormalities. These results demonstrate that SCI results in total, but reversible, regression of spermatogenesis. Failure to prevent such effects by an otherwise effective exogenous testosterone regimen suggests that non‐endocrine factors are involved in the SCI effects on spermatogenesis. The unusual Sertoli cell localization in the regressed testes may have been triggered by the loss of proliferating spermatogonia and may be involved in subsequent spermatogenic recovery.
Oxidative Stress Differentially Regulates the Expression of γ‐Glutamyl Transpeptidase mRNAs in the Initial Segment of the Rat Epididymis
Authors: MARKEY CAROLINE M. , RUDOLPH DANIEL B. , LABUS JACQUELYN C. , HINTON BARRY T.
Published: October 2023

ABSTRACT: Reactive oxygen species (ROS) have a powerful cytotoxic effect on spermatozoa and have been implicated in spermatozoal dysfunction and male infertility. γ‐Glutamyl transpeptidase (GGT) is essential to the metabolism of the antioxidant glutathione and, as such, is believed to be important in protecting spermatozoa against oxidative stress. The aims of this study were 1) to establish in vitro conditions in which ROS were generated and 2) to determine whether oxidative stress regulated the expression of GGT mRNAs I—IV in the initial segment of the epididymis. Initial segments were collected from adult male rats and incubated in culture media to which ROS‐generating compounds, hypoxanthine and xanthine oxidase, were added. By 6.5 hours, incubation of tissue in high—oxidative stress conditions caused a 56% decrease in reduced glutathione concentration, a concomitant 240% increase in oxidized glutathione concentration, and a 25% decrease in adenosine triphosphate concentration. RNase protection analyses demonstrated an approximate 70% up‐regulation of GGT mRNAs II—IV in a differential manner, depending on the concentration of oxidizing agents and the type of ROS generated. γ‐Glutamyl transpeptidase mRNA I was not expressed. These results support the hypothesis that expression of GGT mRNAs is regulated by oxidative stress in the initial segment of the rat epididymis.
Gonadal and Pituitary Responsiveness of Stallions is not Down‐Regulated by Prolonged Pulsatile Administration of GnRH
Authors: BRINSKO STEVEN P. , SQUIRES EDWARD L. , PICKETT BILL W. , NETT TERRY M.
Published: October 2023

ABSTRACT: The objective of this study was to determine if prolonged pulsatile administration of homologous gonadotropin‐releasing hormone (GnRH) at therapeutic or 5x therapeutic doses would cause down‐regulation of the stallion's hypothalamic‐pituitary‐testicular axis. Fifteen stallions were randomly assigned to three treatment groups (n = 5/group) and received a 0.5 ml subcutaneous dose of saline (group 1), 50 μg GnRH (group 2), or 250 μg GnRH (group 3) every 2 hours for 75 days. Weekly evaluations of follicle stimulating hormone, luteinizing hormone, and testosterone and monthly evaluations of daily sperm output and spermatozoal motility failed to demonstrate any decreased pituitary or gonadal responsiveness within or among treatment groups (P > 0.1) as a result of treatment with GnRH. Results of this study demonstrate that the hypothalamic‐pituitary‐testicularaxis of the stallion, unlike that of other domestic species, is remarkably refractory to GnRH‐induced down‐regulation.
Motility Potential of Macaque Epididymal Sperm: The Role of Protein Phosphatase and Glycogen Synthase Kinase‐3 Activities
Authors: SMITH GARY D. , WOLF DON P. , TRAUTMAN KEVIN C. , VDAYARAGHAVAN SRINIVASAN
Published: October 2023

ABSTRACT: Human and monkey ejaculated sperm contain protein phosphatase‐1 (PP1), PP1 inhibitor 2 (12), and glycogen synthase kinase‐3 (GSK‐3). Inhibition of ejaculated human sperm protein phosphatase (PP) activity with calyculin‐a (CL‐A) significantly stimulates motility, implicating protein dephosphorylation in motility regulation. The present experiments were conducted to characterize and compare PP and GSK‐3 activity in monkey caput and caudal epididymal sperm, to determine the cellular distribution of these enzymes, and to test the thesis that epididymal sperm PP activity is inversely related to motility. Caput epididymal sperm populations, (8.8% motile) contained levels of PP activity that were >3 times as high as those of caudal spermatozoa. This PP activity was further identified by inhibitor response profiles as PP1. In both caput and caudal sperm, the majority of this PP1 activity was localized in 100,000 × g soluble fractions. Western blot analysis indicated that a portion of this difference was the result of elevated amounts of PP1 in caput compared with caudal epididymal sperm. The presence of GSK‐3 activity was undetectable in 100,000 × g insoluble fractions of epididymal sperm, whereas both caput and caudal sperm soluble fractions contained GSK‐3 activity, which was approximately threefold higher in caput sperm compared with caudal populations. Treatment of caput epididymal sperm from the rhesus macaque with the PP inhibitor CL‐A resulted in a significant, dose‐dependent increase from 8 to 38% motile cells (without any effect on their path velocity). In contrast, CL‐A had no significant influence on either percent motility or path velocity of caudal epididymal sperm. Cytosolic PP1 and GSK‐3 activities appear to be inversely related to the motility of monkey epididymal sperm and may have a regulatory role in the development of the potential for motility in epididymal sperm.
Effect of Acute Androgen Withdrawal by GnRH Antagonist on Epididymal Sperm Motility and Morphology in the Cynomolgus Monkey
Authors: YEUNG CHING‐HEI , WEINBAUER GERHARD F. , COOPER TREVOR G.
Published: October 2023

ABSTRACT: Hormonal male contraception requires an induction phase before azoospermia and contraceptive safety are achieved. The nature of spermatozoa that may be ejaculated during this induction phase was studied in a nonhuman primate. The GnRH antagonist Cetrorelix was administered daily to five cynomolgus monkeys to induce testicular regression, and the vehicle was given to five control animals. Within 16 days. the antagonist reduced androgens by 80% in the serum and by 50% in the epididymis. Sperm were obtained by mincing different epididymal regions and were examined for morphology (subjectively) and motility (objectively) after removal of the organs 16 and 25 days after continuous treatment. Spermatozoa entering the epididymis of monkeys undergoing regression differed from those of vehicle‐treated controls in their greater susceptibility to disruption during preparation for morphological staining. The acquisition of motility by sperm in the epididymides attached to regressing testes occurred in the same epididymal region as controls but did not achieve the median velocities attained by sperm in controls during epididymal passage. Values for most sperm motion parameters developed as in the controls, and, during epididymal passage, sperm developed resistance to stresses encountered during preparation for morphological analysis. Those observations suggest that spermatozoa ejaculated before spermatogenesis ceases may be potentially fertilizing because epididymal maturation continues in an androgen‐deprived organ. From these preclinical studies, it can be concluded that in men, applying hormonal contraception precautions against pregnancy must be recommended before azoospermia is induced, since the epididymis can partially compensate for poor‐quality sperm produced by a regressing testis even when levels of circulating androgens and tissue androgens are low.