Fibromuscular Wall Research Articles

A true congenital pancreatic cyst in a dog

BackgroundTrue congenital pancreatic cysts are a rare pathological process reported within feline and human literature. To date there has been no documented case of a true congenital cyst affecting a canine patient. The objective of this case report is to document the clinical findings, diagnostic investigations, surgical treatment, histopathological diagnosis and long-term outcome of a dog with a true pancreatic cyst.Case presentationA 5-month-old crossbreed dog was presented with a six-week history of abdominal pain, apparent bilateral pelvic limb weakness, reluctance to walk and intermittent vomiting and diarrhoea. An abdominal ultrasound examination performed by the dog’s primary care veterinarian identified a large intra-abdominal structure of unclear origin. A computed tomographic examination identified a large ovoid structure measuring 156 mm in length, 95 mm in height and 89 mm in width and apparently originating from the left limb of the pancreas. An exploratory coeliotomy was performed and a partial pancreatectomy was performed to allow complete removal of the cystic structure. Histopathological analysis of sections of the wall of the large fluid-filled cyst identified a thick fibromuscular wall lined by a well regimented hyperplastic tall columnar epithelium with basally located round to ovoid nuclei featuring fine chromatin stippling and abundant apically located and surface mucin, concurrent with a true congenital pancreatic cyst. A long-term follow-up of twenty-nine months identified no clinical signs of recurrence.ConclusionA partial pancreatectomy and en bloc excision of a true pancreatic cyst provided an excellent long-term outcome in a dog.

FGFR2 signaling enhances the SHH-BMP4 signaling axis in early ureter development.

The patterned array of basal, intermediate and superficial cells in the urothelium of the mature ureter arises from uncommitted epithelial progenitors of the distal ureteric bud. Urothelial development requires signaling input from surrounding mesenchymal cells, which, in turn, depend on cues from the epithelial primordium to form a layered fibro-muscular wall. Here, we have identified FGFR2 as a crucial component in this reciprocal signaling crosstalk in the murine ureter. Loss of Fgfr2 in the ureteric epithelium led to reduced proliferation, stratification, intermediate and basal cell differentiation in this tissue, and affected cell survival and smooth muscle cell differentiation in the surrounding mesenchyme. Loss of Fgfr2 impacted negatively on epithelial expression of Shh and its mesenchymal effector gene Bmp4. Activation of SHH or BMP4 signaling largely rescued the cellular defects of mutant ureters in explant cultures. Conversely, inhibition of SHH or BMP signaling in wild-type ureters recapitulated the mutant phenotype in a dose-dependent manner. Our study suggests that FGF signals from the mesenchyme enhance, via epithelial FGFR2, the SHH-BMP4 signaling axis to drive urothelial and mesenchymal development in the early ureter.

Ureteric diverticulum: A diagnostic challenge

Ureteric diverticulum is a rare urological condition with only 47 cases described in the literature till 2013. A full term female infant presented with a huge cystic lump occupying almost the entire right side of the abdomen at 1 month of age. Ultrasonography and Magnetic Resonance Urography (MRU) revealed right sided gross hydronephrosis with pelvis appeared folded onto itself along with left sided mild hydronephrosis. On EC scan, differential function of right sided kidney was 0.9%. With working diagnosis of right sided giant hydronephrosis secondary to pelviureteric junction obstruction, the child was posted for Anderson - Hynes pyeloplasty through right flank incision. On exploration we were surprised to find ureteric diverticula. Excision of ureteric diverticulum with proximal ureterostomy was done. Distal part of ureter was transfixed. Histopathological examination of diverticulum showed presence of fibromuscular wall suggestive of true diverticulum. Since ureterostomy was draining only few drops of clear fluid and on repeat EC scan there was no improvement in function of right kidney, right nephroureterectomy was done after 6 months.

Malignant peripheral nerve sheath tumor of the uterine cervix expressing both S‐100 protein and HMB‐45

A 50-year-old woman presented with a large cervical polypoid mass. Grossly, the mass occupied a substantial proportion of the cervical canal, measuring 6 cm. Histologically, the mass showed a spindle cell malignancy arranged in large fascicles that penetrated deeply into the fibromuscular wall of the cervix. The spindle cells were immunoreactive for both S-100 protein and HMB-45 antigen, but were negative for Melan-A. Electron microscopy showed that cytoplasmic processes of the spindle to oval tumor cells contained microtubules and were lined by basal lamina and abundant intercellular collagen spacing with no melanosomes in any stage. As far as we are aware, this is the ninth reported case of cervical malignant peripheral nerve sheath tumor (MPNST), and the second reported case of MPNST expressing HMB-45 antigen.

Ecophysiological responses of the seminal vesicle of Libyan jird (Meriones libycus) to the Saharan conditions: histological, morphometric and immunohistochemical analysis.

The Libyan jird (Meriones libycus) is a nocturnal Saharan Rodent submitted to a seasonal cycle of reproduction characterized by a short active period during spring and beginning of summer, and a long phase of sexual quiescence from the end of summer until the end of winter. During this cycle, the male reproductive organs, and more particularly seminal vesicles, experience some important weight and histological variations. During the breeding period, the wall of each seminal vesicle describes several folds radiating inside a broad lumen filled with a very abundant secretion. The wall is limited with high columnar epithelial cells surrounded with extracellular matrix restricted to some connnective fibres located in the narrow axis of the folds and in the chorion. The fibro-muscular wall is narrow. During sexual quiescence, the seminal vesicles regress. No secretion has been observed inside the lumen. The wall of lumen is now surrounded with a single cubic epithelium. The persistent epithelial folds possess a wide axis. The hypertrophied extracellular matrix is constituted with a very tight and abundant connective tissue. The fibro-muscular wall is thick. A quantitative morphometric study was performed with automatic image analysis that allowed to quantify the seasonal variations of the histological components. The numerical values obtained agree with the histological images observed, the epithelial surface area (microm2) is high in spring and significantly weak during sexual quiescence. The stroma and the fibro-muscular wall occupy an important surface area on sections during the resting period compared with the value collected during the active phase. The study of the apoptosis by TUNEL method revealed the presence of a considerable number of apoptotic nuclei in the epithelial fraction during the resting phase. The indirect immunohistochemical method allowed us to visualize the presence of types I and III collagen in the extracellular matrix, weak during the period of breeding, intense and diffuse during the resting season like in castrated Meriones libycus.

Cases of ectopic pregnancies as seen in Lagos State University Teaching Hospital, Ikeja, Nigeria

Objective : To determine the prevalence rate, the major forms of ectopic pregnancy and to correct some of the inadequacies in filling of the laboratory forms. Materials and Methods : Relevant data on 91 ectopic pregnancy specimens received at the Lagos State University Teaching Hospital (LASUTH), Ikeja between May 1 2001 and 30 November 2004 were collected from the laboratory forms and analyzed. Results>/b>: A total of 91 ectopic pregnancy cases were received during the 3 year period. The total gynaecological and pregnancy-related specimens were 613 and 472 respectively. Ectopic pregnancy accounted for 14.4% of all the gynaecological and 19.28% of pregnancy-related specimens received in the laboratory. The ages of the patients presenting with ectopic pregnancies ranged from 17 to 36 years with the age group 25 – 29 years representing the highest percentage of 51.6%. The ages of the patient studied were not recorded in 62.2% of cases. 96.70% of the pregnancy specimens were tubal while ovarian occurred in 3.3% of cases. Each of the fallopian tubes had 50% chance of being involved. The sites of the tubal ectopic pregnancy were not specified in 73.2% of cases. A case of bilateral ectopic pregnancy was received. The tubes were recorded as having ruptured in 37.8% of cases. Results showed that lymphocytes are the commonest inflammatory cells seen in the fibro-muscular wall of the fallopian tubes. Conclusion : The rate of ectopic pregnancy is on the increase in Lagos(1). The high rate of tubal rupture associated with ectopic pregnancy can be reduced through the creation of better awareness of this condition in the society, as this will ensure early presentation and referral of cases to hospital. Doctors should be encouraged to fill the relevant portions of the laboratory forms correctly before sending specimens to the laboratories. Keywords : Ectopic pregnancy, Incidence rate, Histopathological laboratory forms Nigerian Journal of Health and Biomedical Sciences Vol. 5 (2) 2006: 79-82

Reconsideration of the Histologic Definitions Used in the Pathologic Staging of Extrahepatic Bile Duct Carcinoma

The histologic boundaries of the extrahepatic bile ducts (EBDs) are not well defined, despite the fact that pathologic staging of carcinomas arising in these structures requires the determination of extent of tumor invasion in this area. Perhaps in part, because the smooth muscle band in the EBD wall is not well formed throughout the length of these structures, a previous definition of the outer portion of the bile duct wall included "loose, richly vascularized connective tissue, interlaced with large nerve fibers." We have experienced difficulty in the application of these criteria in staging EBD carcinomas, which requires the histologic determination of the extent of the EBD wall. To systematically study the histologic features of EBD tissue boundaries, 34 EBD specimens obtained from autopsy were analyzed with attention to the distribution of blood vessels and nerve fibers along the length of this system. The EBD specimens were divided into lower, middle, and upper portions, and the locations of blood vessels and nerve fibers were then analyzed separately at each location. We defined the fibromuscular wall as the dense concentric arrangement of collagen and smooth muscle fibers surrounding the EBD mucosa. The location of blood vessels and nerve fibers was categorized as either (1) within, (2) junctional to, or (3) outside of the fibromuscular wall. Blood vessels and nerve fibers are located predominantly outside of the fibromuscular wall and are usually surrounded by adipose tissue throughout the entire EBD, however, their distribution in this location is not consistent. Because of these histologic features, we propose that the bile duct wall is more precisely defined as occurring between the mucosa and the outermost boundary of dense fibromuscular tissue, without consideration of the presence or absence of blood vessels and nerve fibers.

Mesenchymal-epithelial interactions in bladder smooth muscle development: epithelial specificity.

We previously showed that mesenchymal-epithelial interactions are necessary for the development of bladder smooth muscle. Specifically without bladder epithelium embryonic bladder mesenchyme does not differentiate into smooth muscle. We determine whether this process is specific to bladder epithelium or whether epithelial cells from other organ systems induce bladder mesenchyme to differentiate into smooth muscle, as well as whether epithelial age is an important variable. We recombined 14-day bladder mesenchyme before smooth muscle differentiation with rat epithelium from 14-day, 19-day, newborn and adult bladder, ureter, colon, ileum, stomach, cornea and epidermis. In addition, bladder epithelium was recombined with 14-day embryonic small intestinal, 14-day embryonic gastric and newborn seminal vesicle mesenchyme. All tissue recombinants were grafted under the renal capsule of an adult rat syngeneic host for 3 weeks. Immunohistochemical analysis with antibodies directed against smooth muscle alpha-actin revealed that all epithelial types studied induced bladder mesenchyme to differentiate into smooth muscle, although to different degrees. Induction of smooth muscle was independent of urothelial age. In addition, bladder epithelium induced intestinal, gastric and seminal vesicle mesenchyme to differentiate into smooth muscle and express an overall morphological pattern indicative of the bladder fibromuscular wall. The mechanism whereby urothelium induces bladder mesenchyme to differentiate into smooth muscle is not specific to embryonic urothelium. Older urothelium and heterotypic epithelium also induce smooth muscle differentiation. With the common use of bowel, stomach and ureteral segments for bladder augmentation it is important to understand the interaction of different types of epithelium with the native bladder.

MESENCHYMAL-EPITHELIAL INTERACTIONS IN BLADDER SMOOTH MUSCLE DEVELOPMENT: EPITHELIAL SPECIFICITY

Purpose We previously showed that mesenchymal-epithelial interactions are necessary for the development of bladder smooth muscle. Specifically without bladder epithelium embryonic bladder mesenchyme does not differentiate into smooth muscle. We determine whether this process is specific to bladder epithelium or whether epithelial cells from other organ systems induce bladder mesenchyme to differentiate into smooth muscle, as well as whether epithelial age is an important variable. Materials and Methods We recombined 14-day bladder mesenchyme before smooth muscle differentiation with rat epithelium from 14-day, 19-day, newborn and adult bladder, ureter, colon, ileum, stomach, cornea and epidermis. In addition, bladder epithelium was recombined with 14-day embryonic small intestinal, 14-day embryonic gastric and newborn seminal vesicle mesenchyme. All tissue recombinants were grafted under the renal capsule of an adult rat syngeneic host for 3 weeks. Results Immunohistochemical analysis with antibodies directed against smooth muscle alpha-actin revealed that all epithelial types studied induced bladder mesenchyme to differentiate into smooth muscle, although to different degrees. Induction of smooth muscle was independent of urothelial age. In addition, bladder epithelium induced intestinal, gastric and seminal vesicle mesenchyme to differentiate into smooth muscle and express an overall morphological pattern indicative of the bladder fibromuscular wall. Conclusions The mechanism whereby urothelium induces bladder mesenchyme to differentiate into smooth muscle is not specific to embryonic urothelium. Older urothelium and heterotypic epithelium also induce smooth muscle differentiation. With the common use of bowel, stomach and ureteral segments for bladder augmentation it is important to understand the interaction of different types of epithelium with the native bladder.

Symptomatic cysts in otherwise normal lungs of children and adults

The clinical and pathological features of 28 lung cysts resected in the period 1980-1989, excluding those from patients with emphysema elsewhere in their lungs, have been reviewed. In 12 children aged 8 days to 17 years, five cysts were congenital adenomatoid malformations, three were bronchogenic cysts, two were intralobar sequestrations, one was a cystic haemangioma and one resembled the cysts excised from 16 adult patients. This latter group ranged in age from 20 to 62 years and included 11 cigarette smokers and five asthmatics. Twelve of these cysts were intralobar and four were attached by a pedicle to the pleural surface of the lung. All these cysts had a fibromuscular wall showing varying degrees of acute and chronic inflammation. The presence of at least a partial lining of epithelial cells in all the cysts was confirmed using an immunocytochemical marker. The surrounding lung did not show any significant pathology. These cysts are labelled as simple fibromuscular pulmonary cysts. In the childhood cases, a congenital cause could be established in the majority. The pathogenesis of the adult cysts remains unclear. The presence of inflammation in the cyst walls does not necessarily suggest a role for infection, as secondary infection of cysts cannot be ruled out. An aetiological role for local damage due to cigarette smoking or asthma must be taken into consideration.

Effects of Early Exposure to Diethylstilbestrol on Cellular Protein Expression by Mouse Vaginal Epithelium and Fibromuscular Wall

Epithelia and fibromuscular walls were dissociated from the vaginae of ovariectomized BALB/cCrgl mice (ca. 41 days old) exposed neonatally to diethylstilbestrol (DES) or sesame oil and purified by centrifugation through Percoll density gradients. Neonatal exposure to DES caused the vaginal epithelium to become permanently proliferated and partially keratinized; the control epithelium was low cuboidal. The major cellular proteins expressed in each tissue compartment were examined by two-dimensional gel electrophoresis of [35S]methionine-labeled tissues. The epithelia and fibromuscular walls displayed distinctive two-dimensional protein patterns. In the DES-exposed vaginal epithelium, the expression of two proteins (one had a molecular size of 65 kDa and a pl of 6.0, and the other had a molecular size of 38 kDa and a pl of 6.3) was increased, while the expression of three proteins with molecular sizes of 25, 30, and 140 kDa and pls of 5.6, 5.6 and 6.7, respectively, was reduced, relative to the control epithelium. In the DES-exposed vaginal fibromuscular walls, the expression of 9 proteins was increased whereas the levels of 21 specific proteins, distinct from those in the epithelium, were decreased. Thus, long-term tissue-specific alterations in the synthesis of a select number of cellular proteins occur in the DES-exposed vagina.

Steroid binding alterations in tissue compartments of the vagina of control and neonatally diethylstilbestrol-treated adult mice

Steroid binding in both the vaginal epithelium and the vaginal fibromuscular wall (FMW) was compared in control and neonatally estrogen-treated mice. Neonatal treatment with a low dose of the estrogen diethylstilbestrol (DES) had no significant effect on adult estrogen binding within the assayed vaginal compartments; however, this treatment caused a 2-fold increase in the level of cytosolic progestin binding in the vaginal FMW over that in vehicle-treated mice. This low neonatal dose did not affect the level of progestin binding in the vaginal epithelium. In contrast, neonatal treatment with a larger dose of DES caused marked increases in cytosolic progestin binding, decreases in cytosolic estrogen binding, and increases in nuclear estrogen binding within the FMW. Furthermore, as a result of the changes in specific binding induced by the neonatal DES treatment, the degree of the estrogen binding within in each tissue shifted from a predominantly cytosolic site to a nuclear one.

Intriguing Case: Pigmented Melanocytie Schwannoma of the Uterine Cervix

A 47-year-old woman had a lesion of the uterine cervix that presented clinically as a protruding or aborted leiomyoma. Grossly the tumor occupied a substantial portion of the cervical and endocervical region. Histologically it showed a spindle cell neoplasm arranged in large fascicles that penetrated deeply into the fibromuscular wall of the cervix. The tumor cells had abundant pink cytoplasm that contained considerable brown melanin granules confirmed by Fontana's stain. Cytologically nuclear pleomorphism, hyperchromatism, and giant nuclear forms were observed. Mitoses were also seen. Localized nuclear palisading was present. Electron microscopic examination of paraffin-embedded material revealed numerous premelanosomes and opaque granules that were compatible with mature melanosomes, thus confirming melanogenesis in the tumor. Tumor cells exhibited focal projections, and the connective tissue showed abnormal spacing of collagen. Basal lamina material was noted focally on tumor cell surfaces. Immunocytochemistry showed a positive reaction to S-100 protein and HMB-45 in tumor cell cytoplasm.

Cysts (cystadenomas) and tumors of the rete ovarii.

Cysts and tumors of the rete ovarii have been described only rarely and little is known of their pathology. We describe herein 16 cases of cysts (cystadenomas), 2 solid adenomas, and 1 adenocarcinoma of rete ovarii origin. The patients with the cysts were 23-80 years of age (mean age, 59 years). The cysts averaged 8.7 cm in diameter and were characterized by a location in the hilus; a flat, cuboidal, or columnar, usually nonciliated-lining epithelium; crevices along the inner surfaces; and a fibromuscular wall that often contained hyperplastic hilus cells. The cysts showed many similarities to microscopic dilatations of the rete. The rete adenomas were incidental microscopic findings in two women 45 and 68 years of age. They were located in the hilus and were composed of cords and tubules lined by cells resembling closely those of the normal rete. The rete adenocarcinoma occurred in a 52-year-old woman, was bilateral, and could be partly localized to the hilus. Microscopic examination revealed retiform spaces containing papillae and nests of transitional-like epithelium. Criteria for distinguishing cysts and tumors of rete origin from other ovarian tumors are discussed.

Cytosol and nuclear estrogen and progesterone receptors in the rabbit endocervix

This report describes the measurement of estrogen and progesterone receptors in cytosols and nuclear fractions from endocervical tissue components. Unoccupied cytosol estrogen receptor levels as determined by Scatchard analysis of [ 3H]-estradiol binding data indicated a single class of high affinity binding sites for the epithelial-stromal complex ( K D = 0.74 × 10 −9 M). Binding was specific for estrogen (estradiol > estriol > estrone) and unaffected by desoxycorticosterone, dihydrotesterone and progesterone. Assays for total estrogen receptor verified that 71.6 ± 5.3% of this 8S estrogen receptor is in the epithelial-stromal complex while the remaining approximately 28% is localized in the stroma and fibromuscular wall, with the cells of the complex containing the highest receptor concentration. In 5-day pseudopregnant and ovariectomized rabbits compared to estrous rabbits there was a 50% decrease in the cytosol estrogen receptor in the epithelial-stromal complex and a 30% decrease in the concentration of nuclear receptor. Cytosol and nuclear progesterone receptors were measured as an indicator of estrogen action in the rabbit endocervix. Cytosol progesterone receptor concentrations (fmol/mg DNA) in 5-day pseudopregnant and ovariectomized animals were reduced to approximately 35% of the concentration in estrous animals. Nuclear progesterone receptor concentrations decreased 65% in 5-day pseudopregnant and 90% in ovariectomized animals suggesting decreased receptor synthesis. Collectively these data support the concept that the rabbit endocervix may be directly regulated by estrogens.

Cervical changes in pregnancy, labor, and the puerperium

1.A. Changes During Pregnancy.—2.1. Epithelial proliferation was progressive. The squamous lining increased in thickness and became more cornified. The endocervical folds became taller, and the lining cells more active.3.2. The glands appeared larger, more numerous, and their cells more active. Occasionally, hypertrophy and hyperplasia were extreme. In the glandular zone the stroma became edematous and sparse, and it would appear that there was lessened support for the glands.4.3. The fibromuscular wall was comprised of fibrous connective tissue and a few scattered muscle cells. Vascularity became extreme, especially in the outer portion.5.B. Changes After Vaginal Delivery.—6.1. Edema throughout the organ was marked and extensive hemorrhages were noted.7.2. The majority of the specimens show no evidence of denudation of the glandular area as described by Stieve.8.C. Changes During the Puerperium.—9.1. Regression of the lining, stroma, and glands began during the first four days of the puerperium.10.2. Regressive changes in the fibromuscular wall were more marked after the first week.11.D. Associated Changes.—12.1. Decidual changes within the stroma were present in twelve specimens.13.2. Marked epithelial proliferation of the endocervix occurs in healing erosions. In some sections they had a pseudo-malignant appearance. Since the microscopic picture closely resembles early carcinoma, an error in diagnosis may lead to an unnecessary radical operation for this benign condition.14.3. In seven specimens obtained from patients who died of severe toxemia, the squamous lining was unusually thin and not cornified. This is indicative of decreased estrin levels in the blood which accompany late toxemia. It is possible, then, that either vaginal smears or biopsies from the squamous lining of the cervix might make one cognizant of an existing toxemia even before any subjective or objective signs are present.