Banana lectin (BanLec) was isolated from slightly overripe bananas (PCI 6-7) by homogenation in NaCl solution, followed by extraction in the presence of glucose, ammonium sulfate precipitation, and affinity chromatography. Yields were approximately 10-fold greater that those of previously published methods using acidic extraction from very overripe fruit (Peel Color Index [PCI] 7+). By dilution of added isotopically labeled recombinant lectin, the content of total exchangeable BalLec was shown to be constant or to slightly decrease with increasing stage of ripeness, even though extractable BanLec increased, followed by rapid decrease in overripened fruit. In the course of this study we observed that recombinant BanLec expressed in Escherichia coli, although chemically and functionally identical to native BanLec, differed slightly in its apparent molecular size on gel filtration, probably due to differences in its native folding.
The neuroeffectors which relax penile smooth muscle and lead to erection are unknown; physiological studies of human corpus cavernosum, in vitro, have suggested a significant role of cholinergic neurotransmission. To further characterize the importance of cholinergic nerves, biopsies of human corpus cavernosum were obtained at the time of penile prosthesis implantation. Tissues were incubated in /sup 3/H-choline (10/sup -5/M, 80 Ci/mmol) in oxygenated physiological salt solution at 37/sup 0/C, pH 7.4 for 1 hour. Radiolabelled compounds were extracted with perchloric acid (0.4 M) and acetylcholine and choline were separated by HPLC; /sup 14/C-acetylcholine was used as internal standard. /sup 3/H-choline was accumulated by the tissues (20 +/- 1.9 fmol/mg), and /sup 3/H-acetylcholine was synthesized (4.0 +/- 1.1 fmol/mg). In control experiments, heating of the tissue blocked synthesis of /sup 3/H-acetylcholine. Inhibition of high affinity choline transport by hemicholinium-3 (10/sup -5/M) diminished tissue accumulation of /sup 3/H-choline and significantly reduced the synthesis of /sup 3/H-acetylcholine (0.5 +/ 0.2 fmol/mg, p < 0.05). These results provide direct evidence of neuronal accumulation of choline and enzymatic conversion to acetylcholine in human corpus cavernosum. Taken together with the physiological studies, it can be concluded that cholinergic neurotransmission in human corpus cavernosum plays a rolemore » in penile erection.« less
Abstract Introduction In 2004, Bornstein and colleagues performed immunohistochemical (IHC) staining of excised vestibular specimens in patients with vestibular pain. They demonstrated that these specimens contained > 8 CD117 immunopositive stained cells per high-power field (HPF), consistent with mast cells, and excess S100 stained immunopositive cells, consistent with nerves-far more compared to control tissue. However, Bornstein et al. only studied the 1:00-11:00 vestibule in this condition, now referred to as neuroproliferative vestibulodynia (NPV). To the best of our knowledge, the 12:00 region of the vestibule, below the clitoral frenulae and above the urethral meatus, has not been examined with IHC staining. Pain in the 12:00 region can be particularly bothersome for patients and poses several challenges for successful treatment. Objective To report IHC staining findings in the excised 12:00 vestibule specimen and associated clinical characteristics of NPV patients. Methods Retrospective chart review performed. Slides of IHC-stained vestibular tissue specimens from the 12:00 vestibule were examined and high-resolution digital microscopy images were captured under 100x and 200x magnification. A least 2 photomicrographs at both magnifications were taken for each slide that included representative areas of epithelial basement membrane and the adjacent subepithelial regions. Fractional area of positive immunostaining in all photomicrographs was assessed and mean values calculated using computer-assisted histometry by ImageJ. Results A total of 50 patients had complete vestibulectomy including 12:00 and 3 had regional vestibulectomy for only the 12:00 area. Using manual counting as applied by Bornstein et al., 53 excised 12:00 specimens stained for CD117 had a median immunopositive cell count, consistent with mast cells, of 29.5, greater than the described 8 mast cells per HPF. Using computer-assisted histometry, tissue stained for CD117 had a median fractional area of 0.73 in the 12:00 region. Tissues stained for PGP9.5 had a median fractional area of 0.31 in the 12:00 region. Overall, there was no difference between lifelong NPV (LNPV) and acquired NPV (ANPV) patients in the cell count or median fractional area for CD117-immunopositive or PGP9.5-immunopositive staining in the 12:00 region. In LNPV patients who had excision of both the 1:00-11:00 and 12:00 regions, the 12:00 region had significantly less PGP9.5 immunopositive fractional area than the 1:00-11:00 region of the vestibule (p = 0.001). Their H&E pathology findings, including severity grading of the subepithelial inflammatory infiltrate, did not predict the IHC assessment of either CD117 or PGP9.5 in the 12:00 region. The median cotton-tipped swab test pain score was 5 out of 10 for the 12:00 region vs 7 for the rest of the vestibule. Conclusions Current surgical practices often do not include the 12:00 region, likely due to lack of data demonstrating excess mast cells and nerves in this specific region. Our results suggest that there are, in fact, a high density of immunopositive histochemical stains consistent with mast cells and nerves in the 12:00 region and high reported pain scores in both 12:00 and 1:00-11:00 vestibule. Thus, NPV surgical treatments should include, when appropriate, the 12:00 vestibule, as NPV is a field disease involving the entire vestibule. Disclosure No.
BackgroundThe Global Consensus Position Statement on the Use of Testosterone Therapy for Women (Global Position Statement) recommended testosterone therapy for postmenopausal women with hypoactive sexual desire disorder (HSDD).AimTo provide a clinical practice guideline for the use of testosterone including identification of patients, laboratory testing, dosing, post-treatment monitoring, and follow-up care in women with HSDD.MethodsThe International Society for the Study of Women's Sexual Health appointed a multidisciplinary panel of experts who performed a literature review of original research, meta-analyses, review papers, and consensus guidelines regarding testosterone use in women. Consensus was reached using a modified Delphi method.OutcomesA clinically useful guideline following a biopsychosocial assessment and treatment approach for the safe and efficacious use of testosterone in women with HSDD was developed including measurement, indications, formulations, prescribing, dosing, monitoring, and follow-up.ResultsAlthough the Global Position Statement endorses testosterone therapy for only postmenopausal women, limited data also support the use in late reproductive age premenopausal women, consistent with the International Society for the Study of Women's Sexual Health Process of Care for the Management of HSDD. Systemic transdermal testosterone is recommended for women with HSDD not primarily related to modifiable factors or comorbidities such as relationship or mental health problems. Current available research supports a moderate therapeutic benefit. Safety data show no serious adverse events with physiologic testosterone use, but long-term safety has not been established. Before initiation of therapy, clinicians should provide an informed consent. Shared decision-making involves a comprehensive discussion of off-label use, as well as benefits and risks. A total testosterone level should not be used to diagnose HSDD, but as a baseline for monitoring. Government-approved transdermal male formulations can be used cautiously with dosing appropriate for women. Patients should be assessed for signs of androgen excess and total testosterone levels monitored to maintain concentrations in the physiologic premenopausal range. Compounded products cannot be recommended because of the lack of efficacy and safety data.Clinical ImplicationsThis clinical practice guideline provides standards for safely prescribing testosterone to women with HSDD, including identification of appropriate patients, dosing, and monitoring.Strengths & LimitationsThis evidence-based guideline builds on a recently published comprehensive meta-analysis and the Global Position Statement endorsed by numerous societies. The limitation is that testosterone therapy is not approved for women by most regulatory agencies, thereby making prescribing and proper dosing challenging.ConclusionDespite substantial evidence regarding safety, efficacy, and clinical use, access to testosterone therapy for the treatment of HSDD in women remains a significant unmet need.Parish SJ, Simon JA, Davis SR, et al. International Society for the Study of Women's Sexual Health Clinical Practice Guideline for the Use of Systemic Testosterone for Hypoactive Sexual Desire Disorder in Women. J Sex Med 2021;18:849–867.
Hypoactive sexual desire disorder (HSDD) often has a negative impact on the health and quality of life of women; however, many women do not mention-let alone discuss-this issue with their physicians. Providers of gynecologic services have the opportunity to address this subject with their patients.To review the diagnosis and evidence-based treatment of low sexual desire in women with a focus on strategies that can be used efficiently and effectively in the clinic.The Medline database was searched for clinically relevant publications on the diagnosis and management of HSDD.HSDD screening can be accomplished during an office visit with a few brief questions to determine whether further evaluation is warranted. Because women's sexual desire encompasses biological, psychological, social, and contextual components, a biopsychosocial approach to evaluating and treating patients with HSDD is recommended. Although individualized treatment plan development for patients requires independent medical judgment, a simple algorithm can assist in the screening, diagnosis, and management of HSDD. Once a diagnosis of HSDD has been made, interventions can begin with office-based counseling and progress to psychotherapy and/or pharmacotherapy. Flibanserin, a postsynaptic 5-hydroxytryptamine 1A agonist and 2A antagonist that decreases serotonin levels and increases dopamine and norepinephrine levels, is indicated for acquired, generalized HSDD in premenopausal women and is the only agent approved in the United States for the treatment of HSDD in women. Other strategies to treat HSDD include using medications indicated for other conditions (eg, transdermal testosterone, bupropion). Bremelanotide, a melanocortin receptor agonist, is in late-stage clinical development.Providers of gynecologic care are uniquely positioned to screen, counsel, and refer patients with HSDD. Options for pharmacotherapy of HSDD are currently limited to flibanserin, approved by the US Food and Drug Administration, and off-label use of other agents. Clayton AH, Kingsberg SA, Goldstein I. Evaluation and Management of Hypoactive Sexual Desire Disorder. Sex Med 2018;6:59-74.
Leaves from mature Griffonia simplicifolia plants were examined for the presence of leaf lectins possessing sugar binding specificities similar to the four known seed lectins (GS-I, GS-II, GS-III, GS-IV). Three (GS-I, -II, -IV) of the four known G. simplicifolia seed lectins were present in the leaves. Leaf G. simplicifolia lectins I and IV were similar to the respective seed lectins. Leaf GS-II, however, was composed of two types of subunits (M(r) = 33,000 and 19,000), whereas the seed lectin consists of only one type of subunit (M(r) 32,500). Seed and leaf GS-II lectins also had different isoelectric points. All leaf and seed lectins were similar with respect to their hemagglutination and glycoconjugate precipitation properties and all subunits contained covalently bound carbohydrate. Leaf GS-IV appeared slightly under-glycosylated compared to seed GS-IV.The fate of GS-I and GS-II seed lectins in aging cotyledons was investigated. GS-I isolectins usually contain isolectin subtypes associated with each main isolectin. Upon inbibition and germination, these GS-I isolectin subtypes disappeared. Over time, GS-II lectin did not change its disc gel electrophoretic properties.
A lectin specific for chito-oligosaccharides from the exudate of ridge gourd (Luffa acutangula) fruits has been purified to homogeneity by affinity chromatography. The lectin has a molecular weight of 48,000, an S(0)20,w of 4.06 S and a Stokes radius of 2.9 nm. Upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a single band corresponding to Mr of 24,000 was observed both in the presence and absence of beta-mercaptoethanol. The subunits in this dimeric lectin are, therefore, held together solely by noncovalent interactions. The lectin is not a glycoprotein, and secondary structure analysis by CD measurements showed 31% alpha-helix. The hemagglutinating activity of L. acutangula agglutinin was not inhibited by any of the monosaccharides tested. Among the disaccharides only di-N-acetylchitobiose was inhibitory. The inhibitory potency of chito-oligosaccharides increased dramatically with their size up to penta-N-acetylchitopentaose. The lectin has two binding sites for saccharides. The affinity of chito-oligosaccharides for L. acutangula lectin, as monitored by titrating the changes in the near UV-CD spectra and intrinsic fluorescence, increased strikingly with the number of GlcNAc units in them. The values of delta G, delta H, and delta S for the binding process showed a pronounced dependence on the size of the chito-oligosaccharides, indicating that the binding of higher oligomers is progressively more favored thermodynamically than di-N-acetylchitobiose. The thermodynamic data are consistent with an extended binding site in this lectin, which accommodates a tetrasaccharide.
Abstract Female sexual dysfunction is a highly prevalent, multicausal, and multidimensional medical problem that has a major impact on quality of life and interpersonal relationships. It is hypothesized that genital arousal disorder is caused by diminished arterial blood flow within the hypogastric arterial bed. This hypothesis may explain the pathophysiologic mechanisms in older patients with vascular risk factors, but it does not account for either the prevalence or the mechanisms of arousal disorders seen in young women with no vascular risk factors. Hormonal imbalances may be important contributing factors to the pathophysiologic mechanisms involved in female arousal disorders. Androgens modulate the growth and function of female genital sexual organs included the labia, vagina, and clitoris. This article discusses the potential role for androgens in facilitating female genital sexual arousal.
