[Surgery for complicated accessory lobe of the azygos vein]. / Khirurgiya oslozhnennoi dobavochnoi doli neparnoi veny.

Congenital anomalies of respiratory system are quite diverse and not all of them are subject to surgical treatment. One example is accessory lobe of the azygos vein. This anomaly usually has no clinical manifestations and requires only follow-up, as well as attention in surgery on the right half of the chest for some other disease. This situation changes when complications occur, for example, purulent-inflammatory process. Therapy is not always effective, and lung tissue destruction requires surgical treatment. Progressive destruction complicates diagnosis and choosing surgical tactics. We present a rare case of severe purulent-inflammatory complication with abscess in accessory lobe of v. azygos. Anatomical abnormalities following this congenital pulmonary anomaly can cause difficulties in surgeries for other intra-thoracic diseases. The situation is especially relevant for thoracoscopic access. This report will be useful for radiologists, pulmonologists and thoracic surgeons.

Accessory Lobe of Liver: A Rare Hepatic Variation With Diagnostic Dilemma.

The liver is a very dynamic organ. Still, the gross anomalies of the liver are sparse. The accessory lobe of the liver is a rare anatomical variation with a prevalence of less than 1%. We present a case of an accessory lobe and two accessory grooves of the liver in a cadaver. The accessory lobe was an isolated anomaly, sessile in presentation, and attached to normal liver parenchyma. Although accessory lobes are rare, knowledge about them will reiterate to surgeons and radiologists to be mindful of them and to avoid misdiagnosis.

An intrinsic oscillator underlies visual navigation in ants.

Many insects display lateral oscillations while moving, but how these oscillations are produced and participate in visual navigation remains unclear. Here, we show that visually navigating ants continuously display regular lateral oscillations coupled with variations of forward speed that strongly optimize the distance covered while simultaneously enabling them to scan left and right directions. This pattern of movement is produced endogenously and conserved across navigational contexts in two phylogenetically distant ant species. Moreover, the oscillations' amplitude can be modulated by both innate or learnt visual cues to adjust the exploration/exploitation balance to the current need. This lower-level motor pattern thus drastically reduces the degree of freedom needed for higher-level strategies to control behavior. The observed dynamical signature readily emerges from a simple neural circuit model of the insect's conserved pre-motor area known as the lateral accessory lobe, offering a surprisingly simple but effective neural control and endorsing oscillation as a core, ancestral way of moving in insects.

Production of adaptive movement patterns via an insect inspired spiking neural network central pattern generator.

Navigation in ever-changing environments requires effective motor behaviors. Many insects have developed adaptive movement patterns which increase their success in achieving navigational goals. A conserved brain area in the insect brain, the Lateral Accessory Lobe, is involved in generating small scale search movements which increase the efficacy of sensory sampling. When the reliability of an essential navigational stimulus is low, searching movements are initiated whereas if the stimulus reliability is high, a targeted steering response is elicited. Thus, the network mediates an adaptive switching between motor patterns. We developed Spiking Neural Network models to explore how an insect inspired architecture could generate adaptive movements in relation to changing sensory inputs. The models are able to generate a variety of adaptive movement patterns, the majority of which are of the zig-zagging kind, as seen in a variety of insects. Furthermore, these networks are robust to noise. Because a large spread of network parameters lead to the correct movement dynamics, we conclude that the investigated network architecture is inherently well-suited to generating adaptive movement patterns.

Morphologic Variation of Liver Associated With Hourglass Stomach: Case Report and Literature Review.

Ectopic liver tissue is a rare developmental abnormality, and its association with hourglass constriction of the stomach is undocumented to date. This case report describes the discovery of morphologic variations in the liver of an adult female cadaver during routine dissection. The variations include a small, pedunculated, club-shaped accessory lobe covered by a glistening fibrous capsule connecting it to the gallbladder wall, with vessels radiating into the lobe. Two additional lobes were present, one attached to the right upper margin of the caudate lobe, overlapping the inferior vena cava, and another near the quadrate lobe. The right lobe had an abnormal shape with multiple incomplete fissures and furrows. The left lobe was hypoplastic with an elongated end, resembling a lingular process. Further dissection revealed a prominent fibrous band on the posterior surface of the stomach, which continued anteriorly, giving it an hourglass appearance. Knowledge of such variations helps surgeons and radiologists rule out related abnormalities.

A Neural Network for Wind-Guided Compass Navigation.

Spatial maps in the brain are most accurate when they are linked to external sensory cues. Here, we show that the compass in the Drosophila brain is linked to the direction of the wind. Shifting the wind rightward rotates the compass as if the fly were turning leftward, and vice versa. We describe the mechanisms of several computations that integrate wind information into the compass. First, an intensity-invariant representation of wind direction is computed by comparing left-right mechanosensory signals. Then, signals are reformatted to reduce the coding biases inherent in peripheral mechanics, and wind cues are brought into the same circular coordinate system that represents visual cues and self-motion signals. Because the compass incorporates both mechanosensory and visual cues, it should enable navigation under conditions where no single cue is consistently reliable. These results show how local sensory signals can be transformed into a global, multimodal, abstract representation of space.

Surgical management and outcomes of accessory parotid gland neoplasms: A systematic review.

OBJECTIVE: To evaluate surgical approaches and outcomes associated with accessory parotid gland neoplasms. DATA SOURCES: MEDLINE, SCOPUS, and the Cochrane Central Register of Controlled Trials. REVIEW METHODS: A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed. Studies were included if they reported surgical management and outcomes of patients with accessory parotid gland neoplasms. RESULTS: After screening 3532 records, 15 studies were included with a total of 187 patients. Benign tumors consisted of 61.5% of cases. External open, transoral, and preauricular endoscopic approaches were used for 82.3%, 11.3%, and 6.5% of cases, respectively. Accessory lobe resection alone, concurrent with partial parotidectomy, and concurrent with total parotidectomy were used in 54.8%, 43.0%, and 2.2% of cases, respectively. Complication rates were similar between histology groups (7.8% benign vs. 8.3% malignant, p = 0.82). Accessory lobe resection with concurrent partial parotidectomy had the lowest overall complication rate (6.3%). Resections limited to the accessory lobe were found to have an overall complication rate of 8.7%. CONCLUSION: The results offer an overview of the surgical management and complications for accessory parotid gland tumors. Overall surgical complication rates found in these case series may be lower for management of accessory gland tumors than rates available in the literature for tumors within the main parotid gland.

Connecting brain to behaviour: a role for general purpose steering circuits in insect orientation?

The lateral accessory lobes (LALs), paired structures that are homologous among all insect species, have been well studied for their role in pheromone tracking in silkmoths and phonotaxis in crickets, where their outputs have been shown to correlate with observed motor activity. Further studies have shown more generally that the LALs are crucial both for an insect's ability to steer correctly and for organising the outputs of the descending pathways towards the motor centres. In this context, we propose a framework by which the LALs may be generally involved in generating steering commands across a variety of insects and behaviours. Across different behaviours, we see that the LAL is involved in generating two kinds of steering: (1) search behaviours and (2) targeted steering driven by direct sensory information. Search behaviours are generated when the current behaviourally relevant cues are not available, and a well-described LAL subnetwork produces activity which increases sampling of the environment. We propose that, when behaviourally relevant cues are available, the LALs may integrate orientation information from several sensory modalities, thus leading to a collective output for steering driven by those cues. These steering commands are then sent to the motor centres, and an additional efference copy is sent back to the orientation-computing areas. In summary, we have taken known aspects of the neurophysiology and function of the insect LALs and generated a speculative framework that suggests how LALs might be involved in steering control for a variety of complex real-world behaviours in insects.

The occurrence of an additional (accessory) lobe of liver and undescended testis in a single cadaver: a case report.

BACKGROUND: Anatomical variations are common, some of these variations are clinically important and some are not. These variations may require treatment or they may be a variant of a normal presentation. In clinical practices, anatomical variations should not be overlooked. Anatomical variations may cause a tendency to some diseases, and may affect the symptoms, diagnosis and the course of disease. The main objective of this case report is to present the occurrence of two variations observed in a single cadaver. Even though there are reports of individual cases, these combined variations have not been reported before. There is also no evidence of developmental (embryological) circumstances for the liver anomaly to be associated with an undescended testis (cryptorchidism) and vice versa; therefore, this case is, by far, a coincidence. CASE PRESENTATION: The two anatomical variations were noticed in an unclaimed male cadaver used for routine teaching and learning purposes. The Amhara male cadaver was approximate 41-year-old and his clinical history, family history, and other details were unknown. In the first incident, unusually the cadaver's liver consisted of one additional (accessory) lobe situated on the visceral surface of the liver. In the second incident, an undescended testis was observed on the right side near to the superficial inguinal ring. CONCLUSIONS: Overall, knowledge of the above-mentioned anatomical variations has clinical significance to students, researchers, clinicians, surgeons, and radiologists who interpret plain and computed imaging.

Ossified Carcinoma Ex Pleomorphic Adenoma in accessory lobe of parotid gland: Complexity in clinical, imaging and histologic diagnosis and minimally invasive surgery.

Carcinoma ex pleomorphic adenoma is not common among malignant salivary tumors and an accessory lobe of parotid gland tumor with a carcinoma ex pleomorphic adenoma histology is even rarer. Management of these tumors include a high index of suspicion, good understanding of the anatomy and a meticulous surgical access. The exceptional localization of an ossified Carcinoma ex Pleomorphic Adenoma in the accessory lobe of the parotid gland, never reported to date in the literature, has prompted us to report this case to stress the challenging difficulties related to clinical and histologic diagnosis and to analyze a minimally invasive intraoral approach.

Morphology of visual projection neurons supplying premotor area in the brain of the silkmoth Bombyx mori.

Sex pheromones orient male moths toward conspecific female moths; the presence of visual information modulates this behavior. In the current study, we explore candidate neuronal pathways for the interaction between vision and the locomotor signal for pheromone orientation. We describe the connectivity between visual neuropils and brain premotor centers, the posterior slope (PS) and the lateral accessory lobe (LAL), in the silkmoth Bombyx mori. Using a single-cell labeling technique, we analyze visual projection neurons supplying these areas. Neurons from both the medulla and lobula complex projected to the PS but only the neurons originating in the lobula complex had additional processes to the LAL. Further, we identified populations of putative feedback neurons from the premotor centers to the optic lobe. Neurons originating in the PS were likely to project to the medulla, whereas those originating in the LAL were likely to project to the lobula complex. The anatomical study contributes to further understanding of integration of visual information on the locomotor control in the insect brain.

Placenta succenturiata. Reporte de un caso / Succenturiate placenta. Case report

Resumen La placenta succenturiata es una anomalía morfológica de la placenta donde se presentan uno o más lóbulos accesorios por fuera del cuerpo placentario, pueden ser de diferentes tamaños y estar conectados mediante vasos sanguíneos a la placenta principal. El lóbulo accesorio se desarrolla a partir de las vellosidades coriónicas no asociadas al corion leve. La incidencia estimada a nivel mundial es de 1.04% y los principales factores de riesgo asociado a esta entidad son edad materna avanzada y el antecedente de haberse sometido a fertilización in vitro. Presentamos el caso de una paciente de 18 años con diagnóstico de placenta succenturiata con inserción marginal y velamentosa del cordón umbilical, la cual tuvo la finalización de la gestación por parto eutócico en el que se obtuvo recién un nacido eutrófico y sano, con tercer período de trabajo de parto prolongado y retención placentaria, por lo que se realizó alumbramiento manual, y se obtuvo la placenta completa con la presencia de un lóbulo accesorio con conexiones vasculares con el cuerpo placentario. En conclusión, la placenta succenturiata es una anormalidad morfológica relativamente rara, de diagnóstico clínico y morfológico en el puerperio inmediato, sin embargo, debe buscarse de manera intencionada mediante ultrasonido Doppler color en el período prenatal debido a que esta variedad de placenta conlleva a riesgos que pueden comprometer la salud y la vida tanto del feto como de la madre.

Abstract Placenta succenturiate is a morphological anomaly of the placenta where one or more of the lobes are present at a distance, which can be of different sizes and are connected by blood vessels to the main placenta. The accessory lobe develops from the chorionic villi that did not involute from the mild chorion. The estimated incidence worldwide is 1.04%. This entity has been associated with two main risk factors, advanced maternal age and women who have undergone in vitro fertilization. We report the case of a finding of placenta succenturiate in the postpartum period, in an 18-year-old woman in her first pregnancy, with vaginal delivery, eutrophic and apparently healthy newborn was obtained. During the third period of labor the patient presented placental retention, for which manual delivery was performed, obtaining a complete placenta that upon inspection was observed the presence of an accessory lobe in the membranes, which had vascular connections with the main placenta. In conclusion, placenta succenturiata is a relatively rare morphological abnormality, diagnosed in the postpartum period, but it can be diagnosed intentionally by color Doppler ultrasound in the prenatal period. This variety of placenta carries many risks that can compromise the health and life of both the fetus and the mother.

[Saccular aneurysm of the azygos vein in a patient with azygos accessory fissure]. / Aneurisma sacular de la vena ácigos en un paciente con cisura accesoria de la ácigos.

The saccular aneurysm of the azygos vein is an extremely rare condition, which when located in the path of an accesory pulmonary fissure, becomes a diagnostic challenge because it can be mistaken for tumors arising from the accesory pleura, like solitary fibrous tumor of the pleura or mesothelioma. The diagnosis should ideally be done by non-invasive methods such as CT or MR angiographic technique in multiple phases, thus avoiding unnecessary surgical intervention. This case is exceptional because, to our knowledge, it is the first to report both concomitant clinical situations, an aneurysm of the azygos vein in the pathway of its accessory fissure.

Accessory liver lobes: anatomical description and clinical implications.

Accessory liver lobes are a rare condition and appear to be due to excessive development of the liver. The presence of an accessory hepatic lobe is often diagnosed incidentally and sometimes revealed if it develops torsion, especially in pedunculated forms. In most cases, the accessory lobe is located below the liver, i.e., infrahepatic. Riedel's lobe is the best-known example of an accessory lobe, corresponding to hypertrophy of segments V and VI. While accessories lobes can simulate tumors, there have also been reports of hepatocellular tumor(s) that developed in these accessory lobes. Based on a review of the literature, this update focuses on accessory hepatic lobes.

A mini accessory liver lobe in the fissure for ligamentum teres and its clinical significance: a case report.

The liver can present a number of congenital anomalies. More common among them are the irregularities of the shape and the number of lobules. The less common variations include the presence of accessory lobes or accessory livers. The accessory lobes may be attached to the liver through a mesentery or a bridge of the hepatic tissue and they are usually asymptomatic. An accessory liver lobe is a very rare occurrence and when it exists, it becomes clinically important because of its rarity. We are reporting here the presence of a very small accessory liver lobe and have discussed its clinical relevance. We observed a mini liver lobe which was situated in the posterior part of the fissure for ligamentum teres. It was triangular in shape and about one inch in width. It was attached to the left anatomical lobe of the liver through a vascular pedicle which contained the branches of hepatic artery and portal vein and hepatic duct. Histological sectioning revealed the normal liver architecture in the accessory lobe. The knowledge of this accessory lobe could be of use to surgeons and radiologists.

First-generation neuronal precursors in the crayfish brain are not self-renewing.

Adult-born neurons in crayfish (Procambarus clarkii) are the progeny of 1st-generation precursor cells (functionally analogous to neuronal stem cells in vertebrates) that are located in a neurogenic niche on the ventral surface of the brain. The daughters of these precursor cells migrate along the processes of bipolar niche cells to proliferation zones in the cell clusters where the somata of the olfactory interneurons reside. Here they divide again, producing offspring that differentiate into olfactory local and projection neurons. The features of this neuronal assembly line, and the fact that it continues to function when the brain is isolated and perfused or maintained in organotypic culture, provide opportunities unavailable in other organisms to explore the sequence of cellular and molecular events leading to the production of new neurons in adult brains. Further, we have determined that the 1st-generation precursor cells are not a self-renewing population, and that the niche is, nevertheless, not depleted as the animals grow and age. We conclude, therefore, that the niche is not a closed system and that there must be an extrinsic source of neuronal stem cells. Based on in vitro studies demonstrating that cells extracted from the hemolymph are attracted to the niche, as well as the intimate relationship between the niche and vasculature, we hypothesize that the hematopoietic system is a likely source of these cells.

Accessory lobes of the liver: A report of 3 cases and review of the literature.

This article is about 3 cases of accessory lobes of the liver. Case One involved a pedunculated accessory lobe of the liver (ALL), Case Two involved a true ectopic liver, and Case Three involved a sessile accessory lobe of the liver. All 3 cases were diagnosed by computed tomography (CT) or magnetic resonance imaging (MRI) and confirmed by surgical and histological examination. The pertinent literature on accessory lobes of the liver is also reviewed.