Natural products (NPs) have long held a significant position in various fields such as medicine, food, agriculture, and materials. The chemical space covered by NPs is extensive but often underexplored. Therefore, high-throughput and efficient methodologies for the annotation and discovery of NPs are desired to address the complexity and diversity of NP-based systems. Mass spectrometry (MS) has emerged as a powerful platform for the annotation and discovery of NPs. MS databases provide vital support for the structural characterization of NPs by integrating extensive mass spectral data and sample information. Additionally, the released annotation methodologies, based on a variety of informatics tools, continuously improve the ability to annotate the structure and properties of compounds. This review examines the current mainstream databases and annotation methodologies, focusing on their advantages and limitations. Prospects for future technological advancements are then discussed in terms of novel applications and research objectives. Through a systematic overview, this review aims to provide valuable insights and a reference for MS-based NPs annotation, thereby promoting the discovery of novel natural entities.
Biological Products/chemistry* ; Mass Spectrometry/methods* ; Databases, Factual ; Drug Discovery/methods* ; Humans

OBJECTIVETo investigate the clinical reliability of quantitative evaluation by seminiferous tubule scores on spermatogenesis dysfunction, using the testis tissues of azoospermia patients for analysis of histological changes.

METHODSOne hundred and twelve Chinese patients with azoospermia underwent open testicular biopsy and their testicular biopsy specimens were evaluated by 10-score (on testicular biopsy) and 5-Grade (on seminiferous tubule spermatogenesis) scale. The 112 patient, 22 to 46 years old [(29.0 +/- 4.4) years old] included 105 cases of obstructive and 7 cases non-obstructive azoospermia. Of the total number, there were 96 primary infertile cases and 16 secondary infertile cases with infertile marriage of 2-12 years [(4.0 +/- 2.8) years]. Various seminiferous tubule characteristics were categorized by 10-score as follows: [1] degenerating Sertoli cells and no germinal epithelium; [2] no germ cells and only Sertoli cells; [3] no spermatids and primary spermatocytes and only spermatogonia; [4] no spermatids and few primary spermatocytes; [5] no spermatids and numerous primary spermatocytes; [6] no mature spermatids and few round immature spermatids; [7] no mature spermatids and numerous round immature spermatids; [8] < 20 mature spermatids/tubules, germinal epithelium height < 80 microns and spermiation absent; [9] > 20 mature spermatids/tubules, germinal epithelium height < 80 microns and spermiation rarely < 80 microns; [10] > 20 mature spermatids/tubule and germinal epithelium height 80 microns and spermiation common. Seminiferous tubule spermatogenesis was catagorized by 5-Grade scale as follows: [1] tubular sclerosis; [2] sertoli cell only; [3] arrested spermatogenesis; [4] reduced spermatogenesis; [5] intact spermatogenesis.

RESULTSIn terms of the 10-score scale on testicular biopsy, scores of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 corresponded with total patient numbers of 5 (4.5%), 38(33.9%), 2(1.8%), 6(5.4%), 2(1.8%), 17(15.2%), 6(5.4%), 19(17%), 10(8.9%) and 7(6.3%), respectively. According to the 5-Grade scale on the seminiferous tubule spermatogenesis, Grades 1, 2, 3, 4 and 5 corresponded with 5(4.5%), 38(33.9%), 33(29.5%), 29(25.9%) and 7 (6.3%), respectively. Tubular diameter, the thickness of the lamina propria, the height of the germinal epithelium and serum FSH correlated with the average seminiferous tubule scores (P < 0.01).

CONCLUSIONThe seminiferous tubule scores obtained through testicular biopsy may provide important quantitative information concerning the etiology and pathogenesis and of azoospermia may serve as a helpful guide to the fundamental, clinical and therapeutical study of element, clinic and therapy.

Adult ; Follicle Stimulating Hormone ; blood ; Humans ; Male ; Middle Aged ; Oligospermia ; physiopathology ; Seminiferous Tubules ; physiopathology ; Spermatogenesis