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Background: Infertility is a prevalent global condition, and emerging reproductive technologies may enhance its evaluation and treatment. Understanding the current features of randomized clinical trials in infertility is crucial for improving study design and ensuring the translation of results for patient benefits. Objectives: To investigate the primary characteristics of randomized clinical trials related to infertility and areas where require improvement. Materials and methods: We conducted a search on the International Clinical Trials Registry platform for eligible infertility trials between 2003 and 2022. The distribution ratio of various characteristics uploaded by infertility‐related studies on the platform was analyzed and compared according to sex and registration year. Results: Out of the total trials, 85.3% (1,906) included only women, 8.6% (192) included only men, and 6.1% (136) included couples. The majority of retrieved trials followed a parallel arm design (91.0%) and were non‐industry‐funded (92.2%), with a median planned sample size of 131 patients (interquartile range 75–270). Among these trials, 54.5% (1,217) were conducted in Asia. The most common primary purpose of infertility‐related trials was treatment (88.8%), with over half of the investigated interventions focusing on medication (57.9%). Discussion: Asia is the leading region for research, and the drug therapy is still widely used and updated. However, support care for infertile couples has also received some preference. Areas that require improvement and promotion include addressing male infertility and focusing on underserved regions like Africa. The results also highlight deficiencies in trial registration and masking methods, emphasizing the need for better regulation and facilitation of infertility trials in the post‐COVID‐19 era. Conclusion: Based on the current status of infertility RCT studies, greater attention should be paid to infertile men and populations in underdeveloped regions like Africa in future studies, together with a standardized registration and implementation procedures. [ABSTRACT FROM AUTHOR]

As a chemotherapeutic drug, cyclophosphamide (CP) has a negative impact on male fertility due to its reproductive toxicity. Melatonin (Mel) promotes the male reproductive system and increases testosterone synthesis. This study is aimed at exploring the molecular mechanism of Mel as a protector of male fertility against CP-induced cytotoxicity. A CP toxicity model was established in adult ICR male mice by intraperitoneal injection of 100 mg/kg CP every other day for a week. Protective effects of Mel on the testis from CP-induced damage were evaluated using four groups of ICR male mice that received intraperitoneal injections of normal saline, 100 mg/kg CP, 10 mg/kg Mel, or the same dosage of CP and Mel, respectively. Testis morphology was observed by hematoxylin and eosin (HE) staining. Sperm quality parameters were evaluated, and sperm function was studied by in vitro fertilization (IVF). Proliferation, meiosis, and pyroptosis markers were examined by western blot. Results showed that CP treatment induced testis toxicity in a time-dependent manner with the most severe damage to the testis at two weeks post CP treatment. CP-treated mice showed reduced testicular weight and impaired spermatogenesis by downregulating PCNA and SYCP3, reduced serum testosterone levels, decreased sperm counts and motility, increased seminiferous tubule vacuolization, and oxidative damage to spermatogenic cells. All these effects, apart from testicular weight, could be ameliorated by Mel administration. The IVF experiment revealed that CP treatment reduced the rates of sperm fertilization and blastocyst development, which were also enhanced by Mel. Mel-treated mice also showed increased expression of proliferation-associated protein PCNA and meiosis-associated proteins REC8, STRA8, and SYCP3, which were all reduced by CP. Furthermore, Mel inhibited the pyroptosis of spermatogenic cells by reducing GSDMD and IL18 expression. In conclusion, this study indicated that Mel might protect the testis from CP-induced DNA damage to germ cells through the alleviation of pyroptosis. [ABSTRACT FROM AUTHOR]

Chemotherapeutic drug of paclitaxel (PTX) has been shown to cause reproductive toxicity thus affecting male fertility, but its underlying molecular basis is unclear. Melatonin (MLT) can mitigate the reproductive damage caused by certain chemotherapy drugs. In this study, we aimed to identify impact of PTX on the main biological processes and protective effect of MLT on reproductive damage caused by PTX. Mice exposed to PTX mainly impaired spermatogenesis, such as decreased sperm counts, reduced sperm motility and increased abnormal sperm. Decreased expressions of germ cell proliferation‐associated protein PCNA and meiosis‐related protein SYCP3 induced by PTX were determined by Western blot, while MLT ameliorated this effect and increased the expressions of PCNA, SYCP3, DMC1, STRA8 and fertility‐related protein of HSPA2, resulting in significantly improved spermatogenesis and sperm quality levels. In vitro fertilization experiment showed that PTX significantly decreased blastocyst formation rates, which can be improved by MLT administration, but not two‐cell development rates. Taken together, this work demonstrated PTX can adversely affect germ cell proliferation and meiosis, which ultimately influence sperm quality and male fertility, and highlighted the protective ability of MLT on ameliorating the side effects of PTX, especially on sperm quality. The results provide information to further the study on the molecular mechanism of PTX's effects on male reproduction and the protective mechanism of MLT. [ABSTRACT FROM AUTHOR]

Tissue-engineered human anterior hemi-cornea (TE-aHC) is a promising equivalent for treating anterior lamellar keratopathy to surmount the severe shortage of donated corneas. This study was intended to construct a functional TE-aHC with nontransfected human corneal stromal (ntHCS) and epithelial (ntHCEP) cells using acellular porcine corneal stromata (aPCS) as a carrier scaffold, and evaluate its biological functions in a dog model. To construct a TE-aHC, ntHCS cells were injected into an aPCS scaffold and cultured for 3 days; then, ntHCEP cells were inoculated onto the Bowman's membrane of the scaffold and cultured for 5 days under air-liquid interface condition. After its morphology and histological structure were characterized, the constructed TE-aHC was transplanted into dog eyes via lamellar keratoplasty. The corneal transparency, thickness, intraocular pressure, epithelial integrity, and corneal regeneration were monitored in vivo, and the histological structure and histochemical property were examined ex vivo 360 days after surgery, respectively. The results showed that the constructed TE-aHC was highly transparent and composed of a corneal epithelium of 7-8 layer ntHCEP cells and a corneal stroma of regularly aligned collagen fibers and well-preserved glycosaminoglycans with sparsely distributed ntHCS cells, mimicking a normal anterior hemi-cornea (aHC). Moreover, both ntHCEP and ntHCS cells maintained positive expression of their marker and functional proteins. After transplantation into dog eyes, the constructed TE-aHC acted naturally in terms of morphology, structure and inherent property, and functioned well in maintaining corneal clarity, thickness, normal histological structure, and composition in dog models by reconstructing a normal aHC, which could be used as a promising aHC equivalent in corneal regenerative medicine and aHC disorder therapy. [ABSTRACT FROM AUTHOR]

3-Chloro-2-hydroxypropyl dimethyl dehydroabietyl ammonium chloride (CHPDMDHA) was synthesized from dehydroabietylamine (DHA) and epichlorodrin. The synthesis was done in three steps. First, DHA was transformed into N, N-dimethyl dehydroabietyl amine (DMDHA) through Eschweiler-Clarke Reaction. Second, the DMDHA was reacted with hydrochloric acid and translated into DMDHA hydrochloride. Third, the CHPDMDHA was obtained after the DMDHA hydrochloride had reacted with epichlorodrin and recrystallized using a solvent composed of ethyl acetate and ethanol. The critical micelle concentrations (CMC) of CHPDMDHA at 25 °C was found to be 2.56 × 10 mol L, and its surface tension at the CMC (γ) was determined to be 27.4 mN m; these data suggest that the surface activities of CHPDMDHA are better than those of benzalkonium chloride (BC), so that CHPDMDHA could be used as a good alternative to BC. [ABSTRACT FROM AUTHOR]

A novel cationic gemini surfactant with the hydrophenanthrene structure has been synthesized from dehydroabietylamine. Its structure was confirmed by IR, H NMR, and elemental analysis. The critical micelle concentration (CMC) of the surfactant and its surface tension at the CMC ( γ) in aqueous solution were about 1.58 × 10 mol L and 36.6 mN m at 25 °C, respectively. The emulsion composed of equal amounts of benzene and an aqueous solution with 0.1 % gemini surfactant as emulsifier maintained its stability for 8.5 h. Meanwhile, the antimicrobial activities of the gemini surfactant against Pseudomonas aeruginosa, Escherichia aerogenes, and Staphylococcus epidermidis were much better than those of bromogeramine and ampicillin sodium against the same bacteria, and its minimum inhibitory concentrations (MIC) were 16, 32, and 4 μg mL, respectively. [ABSTRACT FROM AUTHOR]

Allyl dimethyl dehydroabietyl ammonium chloride (ADMDHA), as a cationic quaternary ammonium polymerizable antibacterial surfactant, was synthesized from dehydroabietylamine and 3-chloropropene. The structure of ADMDHA was characterized by FT-IR, NMR, and elemental analysis. The critical micelle concentration (CMC) of ADMDHA and the surface tension at the CMC (γ) in aqueous solution were about 2.51 × 10 mol L and 28.5 mN m at 25 °C, respectively. The emulsion consisting of benzene and water with ADMDHA as an emulsifier maintained its stability for 2 days. Meanwhile, the antimicrobial activities of ADMDHA against Escherichia aerogenes and Pseudomonas aeruginosa were much stronger than those of ampicillin sodium and bromogeramine against the same bacteria. [ABSTRACT FROM AUTHOR]

A novel descriptor, referred to as the whitening central projection predictor (WCPD), is developed for affine‐invariant shape description. The proposed descriptor is based on central projection transform (CPT) and whitening transform (WT). Dislike contour‐based or region‐based approaches, an object is first converted to a closed curve by CPT, which is called the general curve (GC). The derived GC not only keeps the affine transform information, but also is very robust to noise. Then WT is performed to the GC with the purpose that the affine transformation is simplified to a rotation only. Finally, Fourier descriptors are employed to remove the rotation, and WCPD is obtained. One advantage of using WCPD for affine‐invariant description lies in that it is applicable to objects consisting of several components. Furthermore, the approach used on the GC is contour‐based, and is of small computational complexity. Several experiments have been conducted to evaluate the performance of the proposed method. Experimental results show that the proposed method has a powerful discrimination ability, and is more robust to noise. [ABSTRACT FROM AUTHOR]

The article focuses on a study on the synthesis and antibacterial activity of 2-hydroxypropyl dimethylbenzylammonium (HPDMBA) N,O-(2-carboxyethyl) chitosan (N,O-2-CEC) chloride. Under the study, chitosan and 3-chloropropionic acid have been used to prepare N,O-2-CEC. Findings show that HPDMBA-CEC displayed better inhibition effect against Staphylococcus (S.) aureus and Escherichia (E.) coli. It adds that HPDMBA-CEC has shown increased antibacterial activity.

The article discusses results of a study that examines the biodegradability and characterization of novel amphoteric superabsorbent polymers (SAP) that were based on elements prepared by inverse suspension copolymerization. A discussion on the swelling behaviors or absorbency in deionized water, hydrogen ion value solutions and saline solutions is provided. Also discussed is the biodegradability of the amphoteric SAPs.

Summary: With the development of the vehicular ad hoc network, the security and privacy are now becoming vital concerns, especially when the attacker owns more and more resources. In order to address these concerns, a dynamic anonymous identity authentication scheme is proposed using Elliptic Curve Discrete Logarithm Problem and blockchain method, which guarantees the security and fast off‐line authentication for vehicle‐to‐infrastructure. Specifically, a dynamic pseudonym key is generated using tamper proof device (TPD) for off‐line authentication and anonymity when a vehicle roams among different roadside units' (RSUs) communication ranges. Even if all RSUs are compromised, vehicle's identity is still privacy. Moreover, two additional design goals are more suitable for the practical environment: (1) the reduced assumption of TPD; (2) certification authority can trace vehicle under the authorization by law. A dynamic anonymous identity authentication scheme is proposed for vehicular ad hoc network, which is more suitable for the practical situation. The analysis and the simulation show that the proposed scheme not only guarantees the offline update, traceable pseudonyms, and anonymous identity authentication, but also improves the efficiency for key pairs dynamically changement. [ABSTRACT FROM AUTHOR]

The title compound, C(6)HCl(6)N, lies on a mirror plane, the asymmetric unit conataining a half-mol-ecule. Weak intra-molecular C-H⋯Cl contacts are observed.

In the title compound, C(25)H(36)N(2)O(2)S, the cyclo-hexane and morpholine rings adopt chair conformations. The cyclo-hexene and cyclo-hexane rings form a trans ring junction with the two methyl groups in axial positions. The N-H and C=O bonds in the urea group are anti to each other. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.

The title compound, C(24)H(34)O(6)·2C(3)H(7)NO, which was isolated from fumaric-modified rosin, has four asymmetrically fused six-membered rings and three carboxylic acid substituents. It contains two fused and unbridged cyclo-hexane rings, which form a trans ring junction with a chair conformation. The asymmetric unit includes one fumaropimaric acid and two dimethyl-formamide mol-ecules. The crystal structure is stabilized through inter-molecular O-H⋯O hydrogen bonds between dimethyl-formamide and fumaropimaric acid.

THE TITLE COMPOUND [SYSTEMATIC NAME: (1R)-methyl 6-bromo-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octa-hydro-phen-anthrene-1-carboxyl-ate], C(21)H(29)BrO(2), was synthesized from N-bromo-succinimide and methyl dehydro-abietate, which was prepared through an esterification reaction using dehydro-abietic acid and methanol as raw materials. The three six-membered rings adopt planar (mean deviation = 0.002 Å) half-chair and chair conformations. The two cyclo-hexane rings form a trans ring junction with the two methyl groups in axial positions. The crystal structure is stabilized by weak inter-molecular C-H⋯O contacts along the b axis.

The title compound, C(20)H(32)O(2), has been isolated from hydrogenated rosin. There are two independent mol-ecules in the asymmetric unit. In each mol-ecule, the cyclo-hexane ring assumes a chair conformation, while the two cyclo-hexene rings adopt half-chair and envelope conformations. Inter-molecular O-H⋯O hydrogen bonding between carboxyl groups links pairs of independent mol-ecules into dimers.

The title compound, C(26)H(37)NO(5), which was synthesized from monoethano-lamine and maleopimaric acid, consists of two fused and unbridged cyclo-hexane rings. They form a trans ring junction with a chair conformation. The two methyl groups are in axial positions. In the crystal, inter-molecular O-H⋯O hydrogen bonds link adjacent mol-ecules into a layer structure. Two C-H⋯O interactions are also present.

THE TITLE COMPOUND [SYSTEMATIC NAME: (1R,4aS,10aR)-7-iso-prop-yl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octa-hydro-phen-anthrene-1-carboxylic acid], C(20)H(28)O(2), has been isolated from disproportionated rosin which is obtained by isomerizing gum rosin with a Pd-C catalyst.. Two crystallographically independent mol-ecules exist in the asymmetric unit. In each mol-ecule, there are three six-membered rings, which adopt planar, half-chair and chair conformations. The two cyclo-hexane rings form a trans ring junction with the two methyl groups in axial positions. The crystal structure is stabilized by inter-molecular O-H⋯O hydrogen bonds.

THE TITLE COMPOUND [SYSTEMATIC NAME: (1R,4aS,10aR,E)-N-benzyl-idene-7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octa-hydro-phenanthren-1-amine], C(26)H(33)N, has been synthesized from nor-dehydro-abietylamine and benzaldehyde. The two cyclo-hexane rings form a trans ring junction with classic chair and half-chair conformations, respectively, the two methyl groups are on the same side of tricyclic hydro-phenanthrene structure. The dihedral angle between two benzene rings is 44.2 (4)°. The C=N bond is in an E configuration.

The title compound {systematic name: 1-[(1R,4aS,10aR)-7-isopropyl-1,2,3,4,4a,9,10,10a-octa-hydro-phenanthren-1-yl]-N-[(E)-2-pyridylmethyleneamino]methanamine}, C(26)H(33)N(2), has been synthesized from dehydro-abietylamine. The two cyclo-hexane rings form a trans ring junction with classic chair and half-chair conformations, respectively, whereas the benzene and pyridine rings are almost planar, and the dihedral angle between them is 80.4°. The two methyl groups directly attached to the tricyclic nucleus are on the same side of the tricyclic hydro-phenanthrene structure.

The title compound, C(17)H(23)NO(2), contains two chiral centres and was synthesized from 2-(3-acetyl-2,2-dimethyl-cyclo-butyl)acetic acid and m-toluidine. The cyclobutane ring is not flat but flexed as though folded from the dimethyl-substituted C atom to the unsubstituted C atom, with a dihedral angle of 25.9°. The crystal structure is stabilized by N-H⋯O and C-H⋯O hydrogen-bonding inter-actions.