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At least 19 recordsLinked to original sources
PubMed1978

[Results of the ciliary body exposure (CBE) in secondary angle closure glaucomas. 1. A clinical study (author's transl)].

The authors present their clinical results of the ciliary body exposure following Benedikt and Hiti. This technique has been performed in 23 patients suffering from secondary angle closure glaucoma. As far as the intraocular tension is concerned good results have been obtained in nearly half of the patients. The results are compared with those of other surgical techniques against secondary angle closure glaucomas.

Aged↗
PubMed1978

[Results of the ciliary body exposure (CBE) in secondary angle closure glaucomas. 2. A histological study (author's transl)].

After treatment of secondary angle closure glaucomas by ciliary body exposure with lamellar scleral resection five eyes had to be enucleated. In view of the histological findings taken from these eyes mode of action and therapeutic value of this operation are considered. The effectiveness of scleral resection seems to be doubtful and there is evidence that permanent regulation of intraocular tension depends mainly on direct diathermy of the ciliary body.

Ciliary Body↗
PubMed1979

Rat gonadotropin release stimulated in vitro by GnRH-depleted rat brain extracts.

A study was made to compare the LH and FSH release patterns from isolated adult rat pituitaries in response to exposure to acidic extracts of rat hypothalamus or brain or to acidic extracts of GnRH-depleted hypothalamus, cerebral cortex, or cerebellum of adult (90-100 days old) or young (14 days old) rats of both sexes, using a continuous perifusion system. Hypothalami of adult rats contained 3-5 ng of radioimmunoreactive GnRH, while the corresponding cerebral cortex and cerebellum contained none, or extremely low levels of GnRH. Adult hypothalamic extract (HE) stimulated considerably greater LH and FSH release than was induced by cortical extract (CE) or cerebellar extract (CBE). Removal of assayable GnRH from HE by incubation with anti-GnRH serum reduced, but did not eliminate, release of both LH and FSH, suggesting that GnRH is the principal but not sole agent responsible for both LH and FSH secretions. Adult male HE released slightly more LH and FSH than did female HE due to its greater GnRH content. GnRH-depleted CE or CBE from both sexes induced LH and FSH releases qualitatively and quantitatively similar to those induced by CE, CBE or GnRH-depleted HE. Untreated extracts or GnRH-depleted extracts of all three brain regions from 14-day-old rats of both sexes induced similar LH and FSH releases as those of adult CE or CBE. Hypothalamus of young rats, which contained about 0.5 ng of immunoassayable GnRH did not release more LH and FSH than the corresponding cortex or cerebellum did. The data indicate that all brain regions so far studied, regardless of sex or age, contained presumably nonspecific substance(s), other than GnRH, capable of stimulating minor but significant LH and FSH releases. Their nature or role in physiological regulation of gonadotropin secretion is unknown, but must be considered, since current concepts, in which GnRH is the sole hypothalamic gonadotropin regulator, are not adequate.

Animals↗
PubMed2025

Transgene-free genome editing in citrus and poplar trees using positive and negative selection markers.

Transgene-free genome editing of the gene of interest in citrus and poplar has been achieved by co-editing the ALS gene via transient transgene expression of an efficient cytosine base editor. CRISPR-Cas genome editing systems have been widely used in plants. However, such genome-edited plants are nearly always transgenic in the first generation when Agrobacterium-mediated transformation is used. Transgene-free genome-edited plants are valuable for genetic analysis and breeding as well as simplifying regulatory approval. It can be challenging to generate transgene-free genome-edited plants in vegetatively propagated or perennial plants. To advance transgene-free genome editing in citrus and poplar, we investigated a co-editing strategy using an efficient cytosine base editor (CBE) to edit the ALS gene to confer herbicide resistance combined with transient transgene expression and potential mobile RNA-based movement of CBE transcripts to neighboring, non-transgenic cells. An FCY-UPP based cytotoxin system was used to select non-transgenic plants that survive after culturing on 5-FC containing medium. While the editing efficiency is higher in poplar than in citrus, our results show that the CBE-based co-editing strategy works in both citrus and poplar, albeit with low efficiency for biallelic edits. Unexpectedly, the addition of the TLS mobile RNA sequence reduced genome editing efficiency in both transgenic and non-transgenic plants. Although a small fraction of escaping plants is detected in both positive and negative selection processes, our data demonstrate a promising approach for generating transgene-free base-edited plants.

Populus↗
PubMed2026

Enhancing CRISPR-Cas12a base editing in plants with LbCas12a variants and introns.

Cytosine base editors (CBEs) and adenine base editors (ABEs) are powerful tools for precise genome editing in plants. Conventionally, such base editors are built upon the CRISPR-Cas9 systems where Cas9 nickases are used. To expand the base editing scope and minimize off-target effects, base editors derived from the CRISPR-Cas12a systems are desired. However, the use of deactivated Cas12a (dCas12a) in such base editors constrains the editing activity, preventing the wide use of Cas12a base editors for plant research and trait development. In this study, we demonstrate the use of an ABE based on the efficient LbCas12a-RRV variant to introduce herbicide-resistant mutations in OsACCase in rice. To improve Cas12a CBEs and ABEs, we inserted introns into the coding sequence of dLbCas12a-RRV. This intron-containing Cas12a-CBE shows substantial improvement in editing efficiency in rice, compared to the intron-less counterparts. By contrast, the improvement of ABE with the intron-containing dLbCas12a-RRV is very limited, partly due to the already high baseline editing efficiency of the intron-less dLbCas12a-RRV ABE. Testing of these base editors in poplar shows elevated C-to-T base editing by dLbCas12a-RRV-intron-CBE. For A-to-G editing, ABEs built upon dLbCas12a-RV and dLbCas12a-RRV variants showed significant improvement over ABEs derived from wild-type LbCas12a and the ttLbCas12a variant. The addition of introns to dLbCas12a-RRV does not further improve the base editing efficiency. With whole genome sequencing in rice, we evaluated genome editing specificities with these improved Cas12a base editors. Our analyses show that both intron-containing Cas12a CBE and ABE barely introduce guide RNA-dependent off-target mutations. However, they can generate guide RNA-independent off-target mutations, which are likely attributed to the high enzymatic activities of the deaminases. Collectively, our study demonstrates the successful use of a Cas12a base editor for trait development and reports improved Cas12a CBEs and ABEs for precise base editing in plants.

Oryza↗
PubMed1979

Capillary and venous blood estrogen in pregnancy.

Total estrogens in the third trimester of pregnancy were measured in matched samples of venous and capillary blood serum. A close correlation was observed between capillary blood estrogens (CBE) and venous blood estrogens (VBE). After establishing norms for CBE during the third trimester of normal pregnancy, the parameter was assessed for its use in high-risk pregnancy in comparison with VBE. In 96.6% of the 59 high-risk pregnancy cases studied, the conclusions drawn about the fetoplacental unit on the basis of CBE and VBE were similar.

Capillaries↗
PubMed2025

An advanced cytosine base editor enabled the generation of cattle with a stop codon in the β-lactoglobulin gene.

β-Lactoglobulin (BLG) is an allergen present in milk that can induce an acute immune response in certain individuals. The successful use of cytosine base editors (CBEs) can introduce stop codons into premature mRNA, thereby generating animals with disrupted genes that negatively regulate target traits. In this study, we employed a CBE system to target the major milk allergen BLG in bovine embryos, mammary epithelial cells, and live cattle. First, the precise single-base editing of the BLG gene in bovine embryos was achieved by designing an effective sgRNA to induce a c.61C > T substitution in the coding region, converting codon 21Gln (p.21Gln) to a premature stop codon. Sanger sequencing revealed an editing efficiency of 83.3% (20 out of 24 embryos), including two homozygous edits. Second, a bovine mammary epithelial cell line harboring BLG edits was constructed using the same CBE system. Sequencing showed that the designed sgRNA1 enabled the simultaneous conversion of three consecutive cytosines (c.59-61CCC > TTT) to thymines. At position c.61, single-cell clones exhibited monoallelic or biallelic editing (BLGc.61C > T), with monoallelic edits at positions c.59 and c.60 (CC > TT). Gene expression analysis confirmed that the BLGc.61C > T mutation effectively suppressed BLG expression at both the mRNA and protein levels, even in monoallelically edited cells. Finally, we successfully generated a heterozygous BLGc.61C > T single-base-edited dairy cow that despite its heterozygosity, showed significantly reduced BLG expression in the mammary epithelial cells and milk. Collectively, this study demonstrates the feasibility of using CBEs to disrupt BLG expression in dairy cows and provides a foundation for application in generating hypoallergenic dairy products.

Animals↗