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Nonfunctioning sellar masses
Published in Nadia Barghouthi, Jessica Perini, Endocrine Diseases in Pregnancy and the Postpartum Period, 2021
They originate from embryonic remnants of Rathke’s pouch which appears on the 24th day of embryonic life:The craniopharyngeal duct forms as Rathke’s pouch extends cranially; meanwhile, the infundibulum forms from the diencephalon as a downgrowth of the neuroepithelium.Between the 3rd and 5th month of gestation, cells in the anterior wall of Rathke’s pouch proliferate to form the anterior pituitary.The infundibulum differentiates into the median eminence, the pituitary stalk, and the posterior pituitary lobe.Failure of obliteration of the craniopharyngeal duct results in the development of a cyst between the pars distalis of the anterior pituitary and the pars nervosa of the posterior pituitary.23
Regulation of Reproduction by Dopamine
Published in Nira Ben-Jonathan, Dopamine, 2020
Human oviducts are long narrow tubes whose main role is to transport the egg from the ovary to the uterus, transport sperm from the vagina and cervix in the opposite direction, and provide a supporting environment for fertilization and early zygote development. The oviduct is not attached to the ovary. Rather, its funnel-shaped structure, the infundibulum, is equipped with finger-like projections, called fimbria, which collect the ovulated egg from the vicinity of the ovary. The ampulla, where fertilization normally occurs, is the widest part of the oviducts and is connected through a narrower isthmus to the uterine cavity. In cross section, the oviduct consists of an innermost ciliated and secretory epithelium, surrounded by outer circular and longitudinal muscles. Both ciliary movement and muscular peristalsis aid in egg and sperm transport.
Cardiology
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
Severity of the symptoms depends on the degree of right ventricular outflow tract obstruction/pulmonary stenosis from the deviated infundibulum. If pulmonary stenosis is severe, there will be neonatal cyanosis; however, generally subvalvar stenosis progresses in infancy resulting in cyanosis developing over the first year of life. As there is a trend to correction in early infancy, it is rare to see clubbing and even the hypercyanotic spells are now uncommon. The latter can present as cyanosis or pallor, frequently on crying. In developing countries where infant correction is not performed, it is not uncommon to see the child assume a squatting position during these spells to alleviate symptoms. This position increases the systemic vascular resistance, reducing the right to left shunting and improving pulmonary perfusion and oxygenation. On examination, infants have an ejection systolic murmur loudest at the upper left sternal edge, this murmur diminishes as right ventricular outflow obstruction increases. There is no murmur associated with the VSD as it is large with equal ventricular pressures on either side. The child may have a parasternal heave and a thrill in the pulmonary area, and the pulmonary component of the second heart sound is quiet.
Artificial hair implantation for hair restoration
Published in Journal of Dermatological Treatment, 2022
Aditya K. Gupta, Maanasa Venkataraman, Emma M. Quinlan
Histopathological studies of artificial fiber implantation provide information on foreign body reaction (FBR), based on the local tissue environment (32,48). For example, the pathology of patients (n = 4) who developed cutaneous complications (erythema, swelling, pustular lesions) post-implantation (2–6 months), revealed infundibulum–like structures (formed by hyperplastic proliferation of epidermal cells around the fiber) with an infiltration of dense inflammatory cells in the superficial and deep dermis (48). On the contrary, the pathology of a patient (n = 1) who did not develop any cutaneous reactions up to 6 months post-implantation showed infundibulum-like structures with the absence of inflammatory cells in the superficial dermis (48). However, both these cases showed fibroplasia along with granulomatous infiltration in the hypodermis and deep dermis (48). This suggests that the implantation of artificial fibers elicits a foreign body reaction. However, the rationale behind the resolution or persistence of cutaneous complications in the host is unclear, as the pathological studies on patient’s post-artificial hair implantation are limited.
Method for adequate macroscopic gallbladder examination after cholecystectomy
Published in Acta Chirurgica Belgica, 2020
Bartholomeus J. G. A. Corten, Wouter K. G. Leclercq, Peter H. van Zwam, Rudi M. H. Roumen, Cees H. Dejong, Gerrit D. Slooter
The gallbladder is a sac-like organ that is divided into the fundus, body, infundibulum (also known as Hartmann pouch), neck and cystic duct. An endoluminal transition surface zone from the neck to the cystic duct may contain undulating folds or valves known as ‘spiral valves of Heister’ [6,7]. A normal gallbladder has a smooth and glistening serosa and is endoluminally lined with folded mucosa [8–11] (Figure 2(a,b)). If intact, the gallbladder is usually filled with green-brown bile. Discolored bile may be indicative of a gallbladder outlet obstruction, either by stones or a tumor. Acute cholecystitis may present as an enlarged and distended gallbladder, with thickened wall with edema and hemorrhage (Figure 2(c,d)), congested vessels, serosal and or mucosal exudate, ulcers with blood clots and or pus. In case of an acute cholecystitis or cholangitis an enlarged lymph node may be situated within the triangle of Calot, known as Mascagni’s or Lund’s node and sometimes erroneously referred to as Calot’s node [12].
Recent advances in follicular drug delivery of nanoparticles
Published in Expert Opinion on Drug Delivery, 2020
Alexa Patzelt, Juergen Lademann
The permanent part of the hair follicle combines the infundibulum, the isthmus and the bulge region. The infundibulum is described as the part of the hair follicle between the skin surface and the sebaceous gland, and provides an intact keratinized epidermis in the upper part. In the lower infundibulum, the differentiation pattern changes from epidermal to trichilemmal with reduced barrier function in the region of the outer root sheath [48]. Especially in this region, a close network of capillaries and dendritic cells surrounds the hair follicle. It can be suggested that substances or xenobiotics that are able to pass the follicular barrier in this region can be immediately recognized by the immune system and evacuated by the blood system. In porcine anagen hair follicles, a continuous tight junction barrier was found from the infundibulum down to the upper suprabulbar region. In the infundibulum, the barrier was found in the stratum granulosum. In the isthmus, bulge and suprabulbar region, the tight junction barrier was localized in the outer root sheath. Additional tight junction barriers were observed between Henle’s and Huxley’s layer of the upper suprabulbar region. In the region of the hair bulb, no barrier can be detected [49,50]. The barrier properties of the hair follicle are schematically presented in Figure 3.