-
Journal of Neurological Surgery. Part... Feb 2018Pediatric skull base and craniofacial reconstruction presents a unique challenge since the potential benefits of therapy must be balanced against the cumulative... (Review)
Review
Pediatric skull base and craniofacial reconstruction presents a unique challenge since the potential benefits of therapy must be balanced against the cumulative impact of multimodality treatment on craniofacial growth, donor-site morbidity, and the potential for serious psychosocial issues. To suggest an algorithm for skull base reconstruction in children and adolescents after tumor resection. Comprehensive literature review and summary of our experience. We advocate soft-tissue reconstruction as the primary technique, reserving bony flaps for definitive procedures in survivors who have reached skeletal maturity. Free soft-tissue transfer in microvascular technique is the mainstay for reconstruction of large, three-dimensional defects, involving more than one anatomic region of the skull base, as well as defects involving an irradiated field. However, to reduce total operative time, intraoperative blood loss, postoperative hospital stay, and donor-site morbidity, locoregional flaps are better be considered the flap of first choice for skull base reconstruction in children and adolescents, as long as the flap is large enough to cover the defect. Our "workhorse" for dural reconstruction is the double-layer fascia lata. Advances in endoscopic surgery, image guidance, alloplastic grafts, and biomaterials have increased the armamentarium for reconstruction of small and mid-sized defects. Skull base reconstruction using locoregional flaps or free flaps may be safely performed in pediatrics. Although the general principles of skull base reconstruction are applicable to nearly all patients, the unique demands of skull base surgery in pediatrics merit special attention. Multidisciplinary care in experienced centers is of utmost importance.
PubMed: 29404244
DOI: 10.1055/s-0037-1615806 -
Seminars in Plastic Surgery Nov 2017Skull base extirpative and reconstructive surgery has undergone significant changes due to technological and operative advances. While endoscopic resection and... (Review)
Review
Skull base extirpative and reconstructive surgery has undergone significant changes due to technological and operative advances. While endoscopic resection and reconstruction will continue to advance skull base surgery for the foreseeable future, traditional open surgical approaches and reconstructive techniques are still contemporarily employed as best practices in certain tumors or patient-specific anatomical cases. Skull base surgeons should strive to maintain a working knowledge and technical skill set to manage these challenging cases where endoscopic techniques have previously failed, are insufficient from anatomical constraints, or tumor biology with margin control supersedes the more minimally invasive approach. This review focuses on the reconstructive techniques available to the open skull base surgeon as an adjunct to the endoscopic reconstructive options. Anatomic considerations, factors relating to the defect or patient, reconstructive options of nonvascular grafts, local and regional flaps, and free tissue transfer are outlined using the literature and author's experience. Future directions in virtual surgical planning and emerging technologies will continue to enhance open and endoscopic skull base surgeon's preparation, performance, and outcomes in this continually developing interdisciplinary field.
PubMed: 29075157
DOI: 10.1055/s-0037-1607273 -
Cureus Jun 2020The role of stereotactic radiosurgery/stereotactic radiotherapy (SRS/SRT) for malignant skull base tumors was summarized and discussed. The treatment of skull base... (Review)
Review
The role of stereotactic radiosurgery/stereotactic radiotherapy (SRS/SRT) for malignant skull base tumors was summarized and discussed. The treatment of skull base tumors remains challenging. Their total resection is often difficult. SRS/SRT is one useful treatment option for residual or recurrent tumors after surgical resection in cases of primary skull base tumors. If skull base metastasis and skull base invasion are relatively localized, they can be candidates for SRS/SRT. Low rates of cervical lymph node involvement in early-stage (N0M0, no lymph node involvement or distant metastasis) nasal and paranasal carcinomas (NpNCa) and external auditory canal carcinomas (EACCa) have been reported in the literature. Such cases might be good candidates for SRS/SRT as the initial therapy. We previously reported the results of SRS/SRT for various malignant extra-axial skull base tumors. In addition, treatment results of early-stage head and neck carcinomas were summarized. Those of our data and those of other reported series were reviewed here to clarify the usefulness of SRS/SRT for malignant extra-axial skull base tumors.
PubMed: 32637280
DOI: 10.7759/cureus.8401 -
Frontiers in Genome Editing 2022Base editors, such as adenine base editors (ABE) and cytosine base editors (CBE), provide alternatives for precise genome editing without generating double-strand breaks...
Base editors, such as adenine base editors (ABE) and cytosine base editors (CBE), provide alternatives for precise genome editing without generating double-strand breaks (DSBs), thus avoiding the risk of genome instability and unpredictable outcomes caused by DNA repair. Precise gene editing mediated by base editors in citrus has not been reported. Here, we have successfully adapted the ABE to edit the TATA box in the promoter region of the canker susceptibility gene from TATA to CACA in grapefruit () and sweet orange (). TATA-edited plants are resistant to the canker pathogen subsp. (). In addition, CBE was successfully used to edit the () gene in citrus. -edited plants were resistant to the herbicide chlorsulfuron. Two -edited plants did not show green fluorescence although the starting construct for transformation contains a GFP expression cassette. The gene was undetectable in the herbicide-resistant citrus plants. This indicates that the edited plants are transgene-free, representing the first transgene-free gene-edited citrus using the CRISPR technology. In summary, we have successfully adapted the base editors for precise citrus gene editing. The CBE base editor has been used to generate transgene-free citrus via transient expression.
PubMed: 35296063
DOI: 10.3389/fgeed.2022.852867 -
Seminars in Plastic Surgery Nov 2020Over the past several decades, endoscopic sinus surgery has revolutionized the approach to skull base surgery. Open skull base approaches remain a viable option for... (Review)
Review
Over the past several decades, endoscopic sinus surgery has revolutionized the approach to skull base surgery. Open skull base approaches remain a viable option for advanced skull base tumors. Complications have gone down with increased reliability of vascularized tissue transfer. In this article, the authors explore the various complications that can present following skull base surgery and review the approaches for repair when such issues are encountered.
PubMed: 33380915
DOI: 10.1055/s-0040-1721765 -
Seminars in Plastic Surgery Nov 2017Traumatic injuries to the skull base can involve critical neurovascular structures and present with symptoms and signs that must be recognized by physicians tasked with... (Review)
Review
Traumatic injuries to the skull base can involve critical neurovascular structures and present with symptoms and signs that must be recognized by physicians tasked with management of trauma patients. This article provides a review of skull base anatomy and outlines demographic features in skull base trauma. The manifestations of various skull base injuries, including CSF leaks, facial paralysis, anosmia, and cranial nerve injury, are discussed, as are appropriate diagnostic and radiographic testing in patients with such injuries. While conservative management is sometimes appropriate in skull base trauma, surgical access to the skull base for reconstruction of traumatic injuries may be required. A variety of specific surgical approaches to the anterior cranial fossa are discussed, including the classic anterior craniofacial approach as well as less invasive and newer endoscope-assisted approaches to the traumatized skull base.
PubMed: 29075156
DOI: 10.1055/s-0037-1607275 -
Cell Systems May 2023Selecting the most suitable existing base editors and engineering new variants for installing specific base conversions with maximal efficiency and minimal undesired...
Selecting the most suitable existing base editors and engineering new variants for installing specific base conversions with maximal efficiency and minimal undesired edits are pivotal for precise genome editing applications. Here, we present a platform for creating and analyzing a library of engineered base editor variants to enable head-to-head evaluation of their editing performance at scale. Our comprehensive comparison provides quantitative measures on each variant's editing efficiency, purity, motif preference, and bias in generating single and multiple base conversions, while uncovering undesired higher indel generation rate and noncanonical base conversion for some of the existing base editors. In addition to engineering the base editor protein, we further applied this platform to investigate a hitherto underexplored engineering route and created guide RNA scaffold variants that augment the editor's base-editing activity. With the unknown performance and compatibility of the growing number of engineered parts including deaminase, CRISPR-Cas enzyme, and guide RNA scaffold variants for assembling the expanding collection of base editor systems, our platform addresses the unmet need for an unbiased, scalable method to benchmark their editing outcomes and accelerate the engineering of next-generation precise genome editors.
Topics: CRISPR-Cas Systems; Gene Editing; Genome; Gene Library; RNA
PubMed: 37164010
DOI: 10.1016/j.cels.2023.03.007 -
Advances in Chronic Kidney Disease Sep 2017Acid-base disorders are in patients with chronic kidney disease, with chronic metabolic acidosis receiving the most attention clinically in terms of diagnosis and... (Review)
Review
Acid-base disorders are in patients with chronic kidney disease, with chronic metabolic acidosis receiving the most attention clinically in terms of diagnosis and treatment. A number of observational studies have reported on the prevalence of acid-base disorders in this patient population and their relationship with outcomes, mostly focusing on chronic metabolic acidosis. The majority have used serum bicarbonate alone to define acid-base status due to the lack of widely available data on other acid-base disorders. This review discusses the time course of acid-base alterations in CKD patients, their prevalence, and associations with CKD progression and mortality.
Topics: Acid-Base Equilibrium; Acid-Base Imbalance; Bicarbonates; Disease Progression; Humans; Prevalence; Renal Dialysis; Renal Insufficiency, Chronic; Risk Factors
PubMed: 29031354
DOI: 10.1053/j.ackd.2017.08.003 -
Advances in Physiology Education Dec 2009Since the topic of the role of the kidneys in the regulation of acid-base balance was last reviewed from a teaching perspective (Koeppen BM. Renal regulation of... (Review)
Review
Since the topic of the role of the kidneys in the regulation of acid-base balance was last reviewed from a teaching perspective (Koeppen BM. Renal regulation of acid-base balance. Adv Physiol Educ 20: 132-141, 1998), our understanding of the specific membrane transporters involved in H(+), HCO(3)(-), and NH(4)(+) transport, and especially how these transporters are regulated in response to systemic acid-base disorders, has advanced considerably. In this review, these new aspects of renal function are presented, as are the broader and more general concepts related to the role of the kidneys in maintaining the acid-base balance. It is intended that this review will assist those who teach this aspect of human physiology to first-year health profession students.
Topics: Acid-Base Equilibrium; Acid-Base Imbalance; Animals; Humans; Kidney; Sodium-Bicarbonate Symporters
PubMed: 19948674
DOI: 10.1152/advan.00054.2009 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Sep 2021In recent years, the genome editing technologies based on the clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) have... (Review)
Review
In recent years, the genome editing technologies based on the clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) have developed rapidly. The system can use homologous directed recombination (HDR) to achieve precise editing that it medicated, but the efficiency is extremely low, which limits its application in agriculture and biomedical fields. As an emerging genome editing technology, the CRISPR/Cas-mediated DNA base editing technologies can achieve targeted mutations of bases without generating double-strand breaks, and has higher editing efficiency and specificity compared with CRISPR/Cas-mediated HDR editing. At present, cytidine base editors (CBEs) that can mutate C to T, adenine base editors (ABEs) that can mutate A to G, and prime editors (PEs) that enable arbitrary base conversion and precise insertion and deletion of small fragments, have been developed. In addition, glycosylase base editors (GBEs) capable of transitioning from C to G and double base editors capable of editing both A and C simultaneously, have been developed. This review summarizes the development, advances, advantages and limitations of several DNA base editors. The successful applications of DNA base editing technology in biomedicine and agriculture, together with the prospects for further optimization and selection of DNA base editors, are discussed.
Topics: Agriculture; CRISPR-Cas Systems; DNA; Gene Editing; Technology
PubMed: 34622618
DOI: 10.13345/j.cjb.200693