A novel site of haematopoiesis and appearance and dispersal of distinct haemocyte types in the Manduca sexta embryo (Insecta, Lepidoptera).

With a set of haemocyte specific markers novel findings on haematopoiesis in the Manduca sexta embryo are presented. We identify a hitherto unknown paired haematopoietic cluster, the abdominal haemocyte cluster in abdominal segment 7 (A7-HCC). These clusters are localised at distinct positions and are established at around katatrepsis. Later in embryogenesis, the A7-HCCs disintegrate, thereby releasing numerous embryonic plasmatocytes which disperse both anteriorly and posteriorly. These cells follow stereotypic migration routes projecting anteriorly. The thoracic larval haematopoietic organs are established at around midembryogenesis. We identify embryonic oenocytoids in the M. sexta embryo for the first time. They appear in the head region roughly at the same time as the A7-HCCs occur and successively disperse in the body cavity during development. Localisation of the prophenoloxidase (proPO) mRNA and of the proPO protein are identical. Morphological, cytometric and antigenic traits show three independently generated haemocyte types during embryogenesis.

Paradigm shift regarding the transversalis fascia, preperitoneal space, and Retzius' space.

BACKGROUND: There has been confusion in the anatomical recognition when performing inguinal hernia operations in Japan. From now on, a paradigm shift from the concept of two-dimensional layer structure to the three-dimensional space recognition is necessary to promote an understanding of anatomy. ANATOMY AND EMBRYOLOGY: Along with the formation of the abdominal wall, the extraperitoneal space is formed by the transversalis fascia and preperitoneal space. The transversalis fascia is a somatic vascular fascia originating from an arteriovenous fascia. It is a dense areolar tissue layer at the outermost of the extraperitoneal space that runs under the diaphragm and widely lines the body wall muscle. The umbilical funiculus is taken into the abdominal wall and transformed into the preperitoneal space that is a local three-dimensional cavity enveloping preperitoneal fasciae composed of the renal fascia, vesicohypogastric fascia, and testiculoeferential fascia. The Retzius' space is an artificial cavity formed at the boundary between the transversalis fascia and preperitoneal space. In the underlay mesh repair, the mesh expands in the range spanning across the Retzius' space and preperitoneal space.

Case Report: Fetal Bilateral Diaphragmatic Agenesis, Ectopic Liver and Abnormal Pancreas.

Congenital bilateral diaphragm agenesis is a very rare condition. We describe limited (abdomen only) autopsy findings of a case of bilateral diaphragm agenesis in a 27-week male fetus with unusual findings of fibrosis of the pancreatic head and ectopic liver nodules in a mass at the upper abdomen that may represent a possible diaphragm anlage. We have correlated our observations with data from experimental and embryological studies to suggest possible mechanisms for the malformations that were present and their implications for our understanding of pancreas, liver and diaphragm development in the human fetus.

The diagnosis and management of intradiaphragmatic extralobar pulmonary sequestrations: a report of 4 cases.

BACKGROUND/PURPOSE: Intradiaphragmatic extralobar pulmonary sequestrations (IDEPSs) are a rare subset of bronchopulmonary sequestrations (BPS). We report the largest series of patients with IDEPS and describe the diagnostic and operative challenges associated with this condition. METHODS: We retrospectively reviewed our experience with fetal and pediatric BPS from 1995 to 2010 to identify patients with IDEPS. RESULTS: We identified 27 patients with BPS and 4 patients in whom the masses were within the diaphragm. In 1 patient, the prenatal ultrasound correctly identified the mass as being within the diaphragm itself, whereas the remaining cases were thought to be intraabdominal or had discordant preoperative imaging findings. The diagnosis of an IDEPS proved challenging to make prospectively using prenatal ultrasound, computed tomography, or magnetic resonance imaging. All patients underwent attempted resection. Two cases required a combined laparoscopic and thoracoscopic approach to accurately localize the mass. The postoperative recovery of these patients was uneventful. CONCLUSIONS: We present the largest reported experience of IDEPS. Because preoperative imaging studies cannot always determine whether a sequestration is intraabdominal, intrathoracic, or intradiaphragmatic, operative planning may pose a challenge. However, the use of minimally invasive approaches can allow exploration of both the thoracic and abdominal cavities with low morbidity.

Peritoneal and retroperitoneal anatomy and its relevance for cross-sectional imaging.

It is difficult to identify normal peritoneal folds and ligaments at imaging. However, infectious, inflammatory, neoplastic, and traumatic processes frequently involve the peritoneal cavity and its reflections; thus, it is important to identify the affected peritoneal ligaments and spaces. Knowledge of these structures is important for accurate reporting and helps elucidate the sites of involvement to the surgeon. The potential peritoneal spaces; the peritoneal reflections that form the peritoneal ligaments, mesenteries, and omenta; and the natural flow of peritoneal fluid determine the route of spread of intraperitoneal fluid and disease processes within the abdominal cavity. The peritoneal ligaments, mesenteries, and omenta also serve as boundaries for disease processes and as conduits for the spread of disease.

Effect of increased intra-abdominal pressure on urinary system development in fetal rabbits.

AIM: To investigate the effect of increased intra-abdominal pressure (IAP) on the fetal urinary system. MATERIALS AND METHODS: Pregnant rabbits (15-day gestation) were used. Control (n = 5) and experimental (EG, n = 4) groups underwent intraperitoneal catheter placement. The IAP was increased by intraperitoneal air insufflations during the third trimester in the EG. At term, organ weight and organ weight/body weight (BW) ratios were noted, histological examination of the urinary system organs was performed, and the apoptotic indexes were calculated. RESULTS: BW and total renal weight were significantly increased in the EG (38.65 ± 8.34 g vs 49.36 ± 8.81 g, p = 0.008; and 0.406 ± 0.132 g vs 0.531 ± 0.129 g, p = 0.02). Total renal weight/BW ratio did not differ between groups (0.0103 ± 0.001 vs 0.0107 ± 0.001; p = 0.33). Bladder weight and bladder weight/BW ratio was also significantly increased in the EG (0.067 ± 0.014 g vs 0.114 ± 0.026 g, p = 0.00; and 0.00175 ± 0.00026 vs 0.00229 ± 0.00036, p = 0.001). Immature glomeruli and collecting tubules, and a thin and underdeveloped muscular layer in the ureter and bladder were encountered in the EG, and the apoptotic cell index was significantly increased (p < 0.05). CONCLUSION: Increased IAP has an adverse effect on fetal urinary system development, and may play a role in the pathogenesis of various congenital abnormalities of the urinary system.

Embryology of the midgut.

In most textbooks of embryology and pediatric surgery, the puzzling spectrum of midgut "malrotations" is explained by an "impaired" process of rotation of the midgut. However, this "process of rotation" is explained in a rather schematic way and aims more to explain pathologic findings whereas detailed embryologic investigations are still rare in this field. Good animal models which would allow the comparison of normal and abnormal midgut development are missing. In this paper we describe the development of the midgut in form of an atlas. Scanning electron microscopy is used in rat embryos to illustrate the crucial embryologic processes of midgut development. The main result shown in these illustrations is that clear signs of a process of rotation are missing.

Accumulation of fetal IgG in immunoglobulin injection into the fetal abdominal cavity is proven.

OBJECTIVE: There have been a number of studies on immunoglobulin injection into fetuses or mothers during pregnancy for the treatment of congenital cytomegalovirus infection. However, no study has examined the effect of injected immunoglobulin on fetal hemodynamics. In this study, we examined the effect of immunoglobulin injection on fetal hemodynamics by retrospectively measuring the concentrations of several igg subclasses in stored umbilical cord blood sera collected during fetal therapy. METHODS: Five patients who underwent immunoglobulin injection into the fetal abdominal cavity (IFAC) as a fetal therapy during pregnancy were included in this study. Frozen-stored umbilical venous blood samples collected from these patients during IFAC were measured for serum concentrations of each IgG subclass. RESULTS: The largest change was observed in the IgG2 concentration, with a mean increase of 221% following IFAC. The IgG4 concentration also showed a mean increase of 63%. In contrast, the concentration of IgG1, which has the strongest physiological activity of all IgG subclasses examined, only exhibited an overall mean increase of 1.4%. CONCLUSION: Our results confirmed that immunoglobulins are incorporated into the fetal circulation following IFAC.

Development of the human retroperitoneal fasciae.

INTRODUCTION: Although the renal fascia (RF), ureteral sheath, lateroconal fascia (LF) and hypogastric nerve are critical landmarks for retroperitoneal surgery, their laminar relationships require clarification. MATERIALS AND METHODS: Horizontal sections (hematoxylin-eosin staining) of human fetuses at two different developmental stages [9-12 (3 fetuses, crown-rump length, CRL 40-65 mm) and 20-25 weeks of gestation (9 fetuses, CRL 152-220 mm)] were compared. RESULTS: In the early-stage group, the pararenal space had already formed between the posterior RF and the transversalis fascia (TF). The anterior RF extended along the peritoneum and often fused with the latter. In the late-stage group, the posterior RF extended inferomedially toward the anterior aspect of the aorta and inferior vena cava. However, at the level of the renal hilus, the posterior RF was connected with vascular sheaths of the great vessels. The LF was seen developing as a fasciculation of the multilaminar structure in the pararenal space. However, on the posterolateral side of the colon after retroperitoneal fixation, the fusion fascia of the peritoneum could also be identified as LF. CONCLUSIONS: A common sheath for ureters and hypogastric nerves appeared to be likely on the inferior side of the kidney. The LF did not appear to be a primary structure such as the RF, but a result of secondary mechanical stress due to fatty tissue developing earlier along the TF than in the perirenal space. However, the suggested similarity between LF and fusion fascia in the plane occupied was a likely cause for misinterpreting the laminar configurations during surgery.

Prenatal ultrasonographic diagnosis of abdominal cystic lymphangioma: a case report.

Abdominal lymphangioma is a rare tumor of the lymphatic vessels. A case of an abdominal cystic lymphangioma identified at 22 weeks of gestation is reported. Ultrasonographic monitoring showed a progressive increase of mass size during the gestation. Pregnancy was terminated at 38 weeks and the newborn was submitted to a laparotomy with resection of all cystic structures. At the present time the infant is three years old and is doing well.

Enteric nervous system development in cavitary viscera allocated to the celiac plexus.

Enteric nervous system (ENS) is a network made of neuronal cells and nervous fibers. There are two plexuses: myenteric of Auerbach and sub mucous of Meissner and Henle. Many substances are involved in neurotransmission at ENS level. ENS assures all gastrointestinal system functions: digestion, absorption, etc. Our study is made on 23 human fetal specimens at different ages of evolution with crown-rump lengths from 9 to 28 cm, and three new born human specimens. We used the Trichrome Masson stain technique and the argental impregnation Bielschowsky on block technique for microscopic evidence. Our study concerned the cavitary viscera allocated to the celiac plexus, involving all layers of each studied viscera.

Intraabdominal fetal echogenic masses: a practical guide to diagnosis and management.

Intraabdominal calcifications and other echogenic masses are relatively common findings during fetal sonography. Many are associated with no additional risk for the fetus or neonate. They may arise from the liver, gallbladder, spleen, kidneys, adrenal glands, gastrointestinal tract, or peritoneal cavity. Detection of such lesions should prompt a detailed survey for additional findings and a review of the maternal history. In some cases, fetal karyotyping may be indicated. In most cases, the diagnosis, management, and outcome are determined according to a combination of specific ultrasound appearances and at least one additional maternal or fetal factor. In utero diagnosis can often be achieved with careful evaluation of the lesion echotexture, associated calcifications, additional findings, and evolution over time. In most cases, expectant management is sufficient, but some patients require transfer to a facility where early postnatal intervention is available. A systematic approach to the findings aids in differential diagnosis and management.