Full-thickness Biopsy Specimens Research Articles

Characteristics of the Cajal interstitial cells and intestinal microbiota in children with refractory constipation

BackgroundChildren with refractory constipation experience intense and persistent symptoms that greatly diminish their quality of life. However, the underlying pathophysiological mechanism responsible for this condition remains uncertain. Our objective was to evaluate characteristics of colonic motor patterns and interstitial cells of Cajal (ICCs) to refractory constipation children, as well as intestinal microbiota compositions. MethodsColonic manometry (CM) was conducted on a cohort of 30 patients with refractory constipation to assess colonic motility, and 7 of them underwent full-thickness colon biopsy specimens. Another 5 colonic specimens from nonconstipation patients were collected to identify the ICCs by immunohistochemistry. Fecal samples from 14 children diagnosed with refractory constipation and subjecting 28 age-matched healthy children to analysis using high-throughput sequencing of 16S rRNA. ResultsAccording to CM results, dividing 30 children with refractory constipation into 2 groups: normal group (n = 10) and dysmotility group (n = 20). Dysmotility subjects showed lower colonic motility. Antegrade propagating pressure waves, retrograde propagating pressure waves, and periodic colonic motor activity were common in normal subjects and rare in dysmotility subjects (32.7 ± 8.9 vs 20.7 ± 13.0/17 h, P < 0.05, 11.5 ± 2.3 vs 9.6 ± 2.3/17 h, P < 0.05, and 5.2 ± 8.9 vs 3.5 ± 6.8 cpm, P < 0.005, respectively), whereas periodic rectal motor activity was more common in dysmotility subjects (3.4 ± 4.8 vs 3.0 ± 3.1 cpm, P < 0.05). Dysmotility subjects exhibited a significantly greater number of preprandial simultaneous pressure waves compared to the normal subjects (32.3 ± 25.0 vs 23.6 ± 13.2/1 h, P < 0.005). Dysmotility subjects displayed a notable decrease in postprandial count of antegrade propagating pressure waves and high amplitude propagating pressure waves when compared to normal subjects (3.9 ± 2.9 vs 6.9 ± 3.5/1 h and 2.3 ± 1.5 vs 5.4 ± 2.9/1 h, respectively, P < 0.05). The number, distribution, and morphology of ICCs were markedly altered in refractory constipation compared children to the controls (P < 0.05). Children diagnosed with refractory constipation displayed a distinct dissimilarity in composition of their intestinal microbiota comparing with control group (P < 0.005). In genus level, Bacteroidetes represented 34.34% and 43.78% in the refractory constipation and control groups, respectively. Faecalibacterium accounted for 3.35% and 12.56%, respectively (P < 0.005). Furthermore, the relative abundances of Faecalibacterium (P < 0.005), Lachnospira (P < 0.05), and Haemophilus (P < 0.05) significantly decreased, whereas those of Parabacteroides (P < 0.05), Alistipes (P < 0.005), Prevotella_2 (P < 0.005), [Ruminococcus]_torques_group (P < 0.005), Barnesiella (P < 0.05), Ruminococcaceae_UCG-002 (P < 0.005), and Christensensenellaceae_R-7_group (P < 0.05) were markedly increased in children with refractory constipation. ConclusionsDysmotility subjects showed lower colonic motility and an impaired postprandial colonic response. The decreased number and abnormal morphology of colonic ICCs may contribute to the pathogenesis of refractory constipation. Children with refractory constipation exhibited significant variations in microbiota composition across various taxonomic levels compared to the healthy control group. Our findings contribute valuable insights into pathophysiological mechanism underlying refractory constipation and provide evidence to support the exploration of novel therapeutic strategies for affected children.

Acellular Dermal Matrix Cover Improves Skin Growth during Tissue Expansion by Affecting Distribution of Mechanical Forces.

Biological cover over tissue expander prostheses has been introduced to provide soft-tissue support for tissue expanders during breast reconstruction. However, its impact on mechanically induced skin growth remains unknown. This study investigates the hypothesis that covering the tissue expander with acellular dermal matrix (ADM) affects mechanotransduction without compromising the efficacy of tissue expansion. Tissue expansion, with and without use of ADM, was performed on a porcine model. The tissue expanders were inflated twice with 45 mL of saline, and the full-thickness skin biopsy specimens were harvested from expanded and control unexpanded skin 1 week and 8 weeks after the final inflation. Histologic evaluation, immunohistochemistry staining, and gene expression analysis were performed. Skin growth and total deformation were evaluated using isogeometric analysis. The authors' results demonstrate that use of ADM as a biological cover during tissue expansion does not impede mechanotransduction that leads to skin growth and blood vessel formation. Isogeometric analysis revealed similar total deformation and growth of expanded skin with and without a biological cover, confirming that its use does not inhibit mechanically induced skin growth. In addition, the authors found that use of an ADM cover results in more uniform distribution of mechanical forces applied by the tissue expander. These results suggest that ADM improves mechanically induced skin growth during tissue expansion by facilitating a more uniform distribution of mechanical forces applied by the tissue expander. Therefore, the use of a biological cover has potential to improve outcomes in tissue expansion-based reconstruction.

Concordance of the Histopathologic Diagnosis of Concurrent Duodenal and Ileal Biopsy Specimens in Dogs.

Simple SummaryCanine chronic inflammatory enteropathy (CIE) is a gastrointestinal (GI) inflammatory condition that requires histopathology of intestinal biopsies for definitive diagnosis. This can be performed endoscopically or surgically; with the former being more common as it is less invasive. In recent years, research has identified that different types of inflammatory disease and histologic severity can exist at different locations within the GI tract, known as discordance. There is a lack of understanding of the clinical impact of lesion oversight in dogs with discordant biopsies between locations. Therefore, current recommendations are to procure endoscopic biopsies from both the upper intestinal (stomach and duodenum) and lower small intestinal tract (ileum) when possible. The rate of discordance between different GI locations has not been assessed in dogs with non-inflammatory enteropathies, i.e., neoplastic etiology, nor compared between endoscopic and surgically collected biopsy specimens. Here, we report that the rate of discordance between the duodenum and ileum in CIE is similar between endoscopic biopsy and surgical biopsy specimens and confirm that discordance between upper and lower GI biopsies exist for small-cell lymphoma. There were no clinicopathologic variables that were correlated with discordance. We conclude that for all dogs with chronic GI signs, concurrent duodenal and ileal biopsies should be performed.Histopathologic discordance between gastrointestinal (GI) locations in canine chronic inflammatory enteropathy (CIE) has prompted recommendations to biopsy both the duodenum and ileum, while further evaluation is required for non-CIE. We aimed to determine the concordance of histopathologic diagnosis between duodenal and ileal endoscopic or full-thickness biopsy specimens for all dogs with CIE and GI neoplasia and to assess the association between histopathologic discordance between GI locations with clinicopathologic variables. Seventy-nine dogs were eligible, with endoscopic (74) or full-thickness (5) biopsy specimens. Clinicopathological data were recorded for all dogs. Concordance of histopathologic diagnosis was retrospectively assessed for concurrent duodenal and ileal biopsy specimens by a single board-certified veterinary pathologist using the modified World Small Animal Veterinary Association (WSAVA) Gastrointestinal Standardization Group guidelines. Sixty-seven dogs were diagnosed with CIE and 5 with enteric-associated T-cell lymphoma-2 (EATL-2). Concordance of histologic diagnosis between duodenal and ileal sites was similar between endoscopic (73.0%) and full-thickness (80.0%) biopsy groups. For the CIE cases, lymphoplasmacytic enteritis had the highest concordance (73.0%) and eosinophilic enteritis the least (16.7%). Of the 5 neoplastic cases, 5/5 (100%) were present at the duodenum but only 3/5 (60%) in the ileum. No clinicopathologic variables demonstrated a statistically significant association with discordance. We conclude that the level of discordance necessitates concurrent biopsy of both duodenum and ileum in all dogs with chronic GI signs. The rate of EATL-2 was lower than rates reported for cats.

Comparing Rectal Biopsy Using Artery Forceps And Full-Thickness Rectal Biopsy In Diagnosing Hirschsprung’s Disease At University Teaching Hospital, Lusaka

Hirschprung’s disease is a congenital disorder characterised by functional constipation whose onset is dependent on the length of the affected bowel and always involves the rectum. Rectal biopsy for histological analysis is the most definitive form of diagnosis. Full-thickness biopsy, which involves full wall laceration under general anaesthesia, continues to be commonly practiced in many African countries, including Zambia. Rectal suction biopsy, which can obtain a superficial-thickness biopsy as deep as the submucosa, has been adopted as the gold standard in the western world, leaving the invasive full-thickness biopsy with its associated risks for inconclusive cases. However, different types of forceps using the grasp and cut method have been shown to be able to obtain superficial-thickness biopsies that are as good or even superior to the rectal suction biopsy. The medium curved artery forceps was proposed to provide a simple, less invasive and hopefully cost-effective method of obtaining superficial rectal biopsies. Thirty-one (31) patients were enrolled in a prospective, single-blind study that was conducted at the University Teaching Hospital in the Department of Surgery, Paediatric Surgical unit from 2018 to 2019. Two biopsy specimens were obtained from each patient in the same sitting using the full-thickness biopsy method and artery forceps and compared the results. Out of 31 patients, 19 (61.30%) of the full-thickness biopsy specimens were adequate for diagnosis, whereas only 4 (12.9%) of the superficial-thickness biopsy specimens using curved artery forceps were adequate. The biopsy obtained using the curved artery forceps had a high sensitivity (93.3%) and poor specificity (13.3%), and predictive value. Although not all patients required suturing hence saving on consumables, none of the patients developed any complications during or after the procedures. Based on these results, the medium curved artery forceps is a poor choice for obtaining rectal biopsies. The traditional full-thickness biopsy procedure should be continued. Efforts should be made to acquire the necessary tools to obtain superficial thickness biopsy and reserve full-thickness biopsy for indeterminate cases.

Japanese clinical practice guidelines for allied disorders of Hirschsprung's disease, 2017.

Despite the presence of ganglion cells in the rectum, some patients have symptoms similar to those of Hirschsprung's disease. A consensus has yet to be established regarding the terminology for these diseases. We defined this group of diseases as "allied disorders of Hirschsprung's disease" and compiled these guidelines to facilitate accurate clinician diagnosis and provide appropriate treatment strategies for each disease. These guidelines were developed using the methodologies in the Medical Information Network Distribution System (MINDS). Of seven allied disorders, isolated hypoganglionosis; megacystis-microcolon-intestinal hypoperistalsis syndrome; and chronic idiopathic intestinal pseudo-obstruction were selected as targets of clinical questions (CQ). In a comprehensive search of the Japanese- and English-language articles in PubMed and Ichu-Shi Web, 836 pieces of evidence related to the CQ were extracted from 288 articles; these pieces of evidence were summarized in an evidence table. We herein outline the newly established Japanese clinical practice guidelines for allied disorders of Hirschsprung's disease. Given that the target diseases are rare and intractable, most evidence was drawn from case reports and case series. In the CQ, the diagnosis, medication, nutritional support, surgical therapy, and prognosis for each disease are given. We emphasize the importance of full-thickness intestinal biopsy specimens for the histopathological evaluation of enteric ganglia. Considering the practicality of the guidelines, the recommendations for each CQ were created with protracted discussions among specialists. Clinical practice recommendations for allied disorders of Hirschprung's disease are given for each CQ, along with an assessment of the current evidence. We hope that the information will be helpful in daily practice and future studies.

Biological differences between functionalis and basalis endometria in women with and without adenomyosis

ObjectiveEndometriosis is commonly believed to originate from functionalis endometrium and adenomyosis from basalis endometrium. Due to the lack of enough information, we investigated the biological differences between these two layers of endometrium in women with and without adenomyosis. Study designThis was a case-controlled study with 12 control women and 17 women with adenomyosis undergoing hysterectomy. Full thickness (extending from the endometrium to the myometrium) biopsy specimens were obtained after the hysterectomy. Based on the phases of the menstrual cycle, the expression patterns of estrogen receptor (ER), progesterone receptor (PR), Ki-67, and activated Caspase-3 were analyzed by immunohistochemistry in the functionalis and basalis endometria. Apoptotic cells were evaluated by TdT-mediated dUTP-biotin nick end-labeling (TUNEL) assay. ResultsA similar pattern of ER and PR expression was found in the functionalis and basalis endometria during the proliferative phase. In contrast, a significantly lower ER and PR expression was found in the basalis endometria than in the functionalis endometria during the secretory phase and the menstrual phase. This was equally observed in control women and in women with adenomyosis. Except Ki-67 indices, TUNEL-positive cells, and expression of activated Caspase-3 were significantly lower in the basalis endometria than in the functionalis endometria during the secretory phase. ConclusionA significant biological difference was found between the functionalis and the basalis endometria derived from women with adenomyosis.

Host response to synthetic mesh in women with mesh complications

Despite good anatomic and functional outcomes, urogynecologic polypropylene meshes that are used to treat pelvic organ prolapse and stress urinary incontinence are associated with significant complications, most commonly mesh exposure and pain. Few studies have been performed that specifically focus on the host response to urogynecologic meshes. The macrophage has long been known to be the key cell type that mediates the foreign body response. Conceptually, macrophages that respond to a foreign body can be dichotomized broadly into M1proinflammatory and M2 proremodeling subtypes. A prolonged M1 response is thought to result in chronic inflammation and the formation of foreign body giant cells with potential for ongoing tissue damage and destruction. Although a limited M2 predominant response is favorable fortissue integration and ingrowth, excessive M2 activity can lead to accelerated fibrillar matrix deposition and result in fibrosis and encapsulation of the mesh. The purpose of this study was to define and compare the macrophage response in patients who undergo mesh excision surgery for the indication of pain vs a mesh exposure. Patients who were scheduled to undergo a surgical excision of mesh for pain or exposure at Magee-Womens Hospital were offered enrollment. Twenty-seven mesh-vagina complexes that were removed for the primary complaint of a mesh exposure (n= 15) vs pain inthe absence of an exposure (n= 12) were compared with 30 full-thickness vaginal biopsy specimens from women who underwent benign gynecologic surgery without mesh. Macrophage M1 proinflammatory vs M2 proremodeling phenotypes were examined via immunofluorescent labeling for cell surface markers CD86 (M1) vs CD206 (M2)and M1 vs M2 cytokines via enzyme-linked immunosorbent assay. The amount of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) proteolytic enzymes were quantified by zymography and substrate degradation assays, as an indication of tissue matrix degradation. Statistics were performed with the use of 1-way analysis of variance with appropriate post hoc tests, t-tests, and Fisher's Exact test. Twenty-seven mesh-vaginal tissue complexes were excised from 27 different women with mesh complications: 15 incontinence mid urethral slings and 12 prolapse meshes. On histologic examination, macrophages surrounded each mesh fiber in both groups, with predominance of the M1 subtype. M1 and M2 cytokines/chemokines, MMP-9 (pro- and active), and MMP-2 (active) were increased significantly in mesh-vagina explants, as compared with vagina without mesh. Mesh explants that were removed for exposure had 88.4% higher pro-MMP-9 (P= .035) than those removed for pain. A positive correlation was observed between the profibrotic cytokine interleukin-10 and the percentage of M2 cells (r= 0.697; P= .037) in the pain group. In women with complications, mesh induces a proinflammatory response that persists years after implantation. The increase in MMP-9 in mesh explants that were removed for exposure indicates degradation; the positive association between interleukin-10 and M2 macrophages in mesh explants that are removed for pain is consistent with fibrosis.

Prevalence and underlying causes of histologic abnormalities in cats suspected to have chronic small bowel disease: 300 cases (2008-2013).

To determine prevalence of histologic abnormalities in cats suspected, on the basis of compatible clinical signs and ultrasonographic findings, to have chronic small bowel disease; identify the most common underlying causes in affected cats; and compare methods for differentiating among the various causes of chronic small bowel disease. Retrospective case series. 300 client-owned domestic cats suspected to have chronic small bowel disease. Medical records were reviewed to identify cats evaluated because of chronic vomiting, chronic small bowel diarrhea, or weight loss that also had ultrasonographic evidence of thickening of the small intestine. Cats were included in the study if full-thickness biopsy specimens had been obtained from ≥ 3 locations of the small intestine by means of laparotomy and biopsy specimens had been examined by means of histologic evaluation and, when necessary to obtain a diagnosis, immunohistochemical analysis and a PCR assay for antigen receptor rearrangement. Chronic small bowel disease was diagnosed in 288 of the 300 (96%) cats. The most common diagnoses were chronic enteritis (n = 150) and intestinal lymphoma (124). Results indicated that a high percentage of cats with clinical signs of chronic small bowel disease and ultrasonographic evidence of thickening of the small intestine had histologic abnormalities. Furthermore, full-thickness biopsy specimens were useful in differentiating between intestinal lymphoma and chronic enteritis, but such differentiation was not possible with ultrasonography or clinicopathologic testing alone.

EUS-guided FNA biopsy of the muscularis propria of the antrum in patients with gastroparesis is feasible and safe

EUS-guided FNA biopsies of the muscularis propria of the gastric wall in patients with gastroparesis could replace the routine use of surgical full-thickness biopsies for assessing the loss of the interstitial cells of Cajal (ICCs) and cellular infiltrates in the myenteric plexus. We investigated the efficacy and safety of EUS-guided FNA biopsies of the muscularis propria of the gastric antrum in gastroparesis and compared the tissue with a surgically obtained full-thickness biopsy specimen in the same patient. This was a prospective, nonrandomized, feasibility trial. Patients with gastroparesis who were undergoing gastric neurostimulator placement were enrolled. Patients had a gastric wall measurement by radial EUS in the body and antrum of the stomach followed by linear EUS examination and FNA of the muscularis propria in the antrum by using a 19-gauge core needle. Within 24 hours, a full-thickness biopsy specimen of the antrum was obtained surgically during neurostimulator placement. Endoscopic and surgical specimens were compared for tissue morphology, number of ICCs (c-kit stain) and enteric neurons (S-100 stain), and fibrosis (trichome) for each patient. The correlation coefficient of the ICC count per high-power field was used to compare both specimens. Continuous data were compared by using a t test. Eleven patients (10 female, 1 male), with a mean age of 40.6 years, were enrolled in the trial. EUS-guided core biopsies were successful in obtaining sufficient tissue for the histologic assessment of ICCs in 9 patients (81%) and for the myenteric plexus in 6 patients (54%). There was a good correlation coefficient (0.65) when both surgical and endoscopic groups were compared for the loss of ICCs. Mild serosal bruising and/or localized hematoma formations were noted at the sites of EUS biopsies, but there were no serosal tears, perforations, or adverse effects on the hospitalization and outcomes. EUS-guided FNA of the gastric muscularis propria in patients with gastroparesis is safe and provides adequate tissue for full histologic assessment. (Clinical trial registration number: NCT01916460.).

Effect of unfocused extracorporeal shock wave therapy on growth factor gene expression in wounds and intact skin of horses

To compare the effect of extracorporeal shock wave therapy (ESWT) on expression of fibroblast growth factor-7 (FGF-7), transforming growth factor-β1 (TGF-β1), insulin-like growth factor-1 (IGF-1), platelet-derived growth factor-A (PDGF), and vascular endothelial growth factor-A (VEGF) in skin with surgically created skin wounds and intact skin in horses. 14 healthy horses. 8 horses were treated with ESWT at 6 locations along the neck at 36, 24, 12, 6, 2, or 1 hour prior to collection of full-thickness biopsy specimens from each location; a control specimen was collected from a sham-treated location. In 6 horses, 5 full-thickness wounds were created in each forelimb. Wounds in 1 forelimb/horse received ESWT immediately after creation and subsequently on days 7, 14, and 21; wounds in the contralateral forelimb remained untreated. Biopsy specimens were collected from 1 wound on each forelimb on days 7, 14, 21, 28, and 35. Expression levels of FGF-7, TGF-β1, IGF-1, PDGF, and VEGF were assessed in tissue samples from the horses' necks and forelimbs. In surgically created wounds, ESWT treatment was associated with reduced TGF-β1 expression, compared with expression in control wounds, during the entire study period. At 28 days following wound creation, IGF-1 expression was significantly increased for treated and untreated wounds, compared with findings on days 7, 14, 21, and 35. There was no significant effect of treatment on FGF-7, TGF-β1, IGF-1, PDGF, or VEGF expression in intact skin. Intervention with ESWT to suppress TGF-β1 may decrease granulation tissue production, resulting in improved wound healing on the distal portion of horses' limbs.

Effect of Topically Applied Minoxidil on the Survival of Rat Dorsal Skin Flap

Flap necrosis still is a challenging problem in reconstructive surgery that results in irreversible tissue loss. This study evaluated the effect of topically applied minoxidil on angiogenesis and survival of a caudally based dorsal rat skin flap. For this study, 24 male Wistar rats were randomly divided into three groups of eight each. A caudally based dorsal skin flap with the dimensions of 9×3cm was raised. After elevation of the flaps, they were sutured back into their initial positions. In group 1 (control group), 1ml of isotonic saline was applied topically to the flaps of all the animals for 14days. In group 2, minoxidil solution was spread uniformly over the flap surface for 7days after the flap elevation. In group 3, minoxidil solution was applied topically to the flap surface during a 14-day period. On day 7 after the flap elevation, the rats were killed. The average area of flap survival was determined for each rat. Subdermal vascular architecture and angiogenesis were evaluated under a light microscope after two full-thickness skin biopsy specimens had been obtained from the midline of the flaps. The lowest flap survival rate was observed in group 1, and no difference was observed between groups 1 and 2. Compared with groups 1 and 2, group 3 had a significantly increased percentage of flap survival (P<0.05). Intense and moderate angiogenesis also was observed respectively at the proximal and distal areas of the flaps in group 3. The results of this experiment seem to show that the early effect of minoxidil is vasodilation and that prolonged use before flap elevation leads to angiogenesis, increasing flap viability. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Treatment of intestinal pythiosis in a dog with a combination of marginal excision, chemotherapy, and immunotherapy

A 1.5-year-old mixed-breed dog was examined because of a 1-month history of anorexia, vomiting, diarrhea, and weight loss. The dog was very thin on physical examination (body condition score, 3/9). Results of all diagnostic tests were within reference limits except intestinal thickening and lymphadenopathy were identified on abdominal ultrasound examination. During exploratory laparotomy, thickening at the ileocecal-colic junction and within the transverse colon and mesenteric lymphadenopathy were identified, and the ileocecal-colic junction was resected. Histopathologic evaluation of the ileocecal-colic junction and full-thickness biopsy specimens from other sites as well as results of a serum ELISA were diagnostic for gastrointestinal Pythium insidiosum infection. Pythiosis was initially treated medically with administration of itraconazole and terbinafine by mouth, but the colonic lesion was progressive with this regimen. Two months after diagnosis, a subtotal colectomy was performed; marginal excision (0.6 cm) was obtained at the aboral margin. The dog was treated with 3 doses of a pythiosis vaccine beginning approximately 2 weeks after surgery and was continued on itraconazole and terbinafine for 5 months. Parenteral and enteral nutrition as well as considerable general supportive care were required postoperatively. Six months after treatment, the dog had a normal serum ELISA titer. Two years after treatment, the dog had returned to preoperative weight and was clinically normal. This patient had an unusually positive therapeutic response to chronic, extensive, marginally excised gastrointestinal pythiosis.

Subcutaneous Approximation Suture for Preventing Soft Tissue Pollybeak Deformity

Pollybeak deformity due to abundant fibrosis formation in the supratip region after rhinoplasty is still a common problem. The aim of this study was to investigate the effects of a modified subcutaneous approximation suture on pollybeak deformity of soft tissue origin. Three groups, each consisting of eight rabbits, were included in the study. Nasal skin was elevated with an open rhinoplasty approach in all groups. During closure of the skin, to minimize supratip dead space, a horizontal subcutaneous approximation suture was used in group I, external tape fixation was used in group II, and no further action was taken for supratip skin approximation in the control group. Full-thickness supratip skin biopsy specimens reaching down to the underlying cartilage tissue were taken from each subject on the 60th day after the operation. Thicknesses of subcutaneous scar tissues were measured histologically in all groups and compared. The mean thickness of the subcutaneous scar tissues was significantly lower (0.98 ± 0.32 mm) in group I than in group II (1.65 ± 0.61 mm; p = 0.036) and the control group (1.72 ± 0.49 mm; p = 0.019). However, there were no significant differences between group II and the control group in the mean thickness of subcutaneous scar tissues (p = 1.000). The findings of this study indicate that the subcutaneous approximation suture is effective for preventing excessive scar tissue formation in the supratip area after rhinoplasty in rabbits. Further clinical studies are needed to determine its efficacy in humans.

Induction of Dermal Collagenesis, Angiogenesis, and Adipogenesis in Human Skin by Injection of Platelet-Rich Fibrin Matrix

To evaluate the histological changes induced in human skin by injection of autologous platelet-rich fibrin matrix (PRFM). Four healthy adult volunteers were included in the study. Platelet-rich fibrin matrix was prepared from 9 mL of autologous blood using a proprietary system (Selphyl; Aesthetic Factors, Wayne, New Jersey) and injected into the deep dermis and immediate subdermis of the upper arms of subjects. Full-thickness skin biopsy specimens were taken from the treated areas over a 10-week period, and the specimens were processed for histological evaluation. Findings from histological examination supported the clinical observation of soft-tissue augmentation. As early as 7 days after treatment, activated fibroblasts and new collagen deposition were noted and continued to be evident throughout the course of the study. Development of new blood vessels was noted by 19 days; also at this time, intradermal collections of adipocytes and stimulation of subdermal adipocytes were noted. These findings became more pronounced over the duration of the study, although the fibroblastic response became much less pronounced. No abnormal mitotic figures were observed at any point, and a very mild chronic inflammatory response was noted only at the earliest time points of the study. Injection of PRFM into the deep dermis and subdermis of the skin stimulates a number of cellular changes that can be harnessed for use. Coupled with prior in vitro and in vivo studies, we now have a much clearer picture of the cellular effects of PRFM and its potential uses in facial plastic surgery. Further work is planned to more clearly elucidate the potential role of PRFM in aesthetic and reconstructive surgery. clinicaltrials.gov Identifier: NCT00956020

Histopathologic Characterization of Chronic Radiofrequency Ablation Lesions for Pulmonary Vein Isolation

This study describes the histopathologic and electrophysiological findings in patients with recurrence of atrial fibrillation (AF) after pulmonary vein (PV) isolation who underwent a subsequent surgical maze procedure. The recovery of PV conduction is commonly responsible for recurrence of AF after catheter-based PV isolation. Twelve patients with recurrent AF after acutely successful catheter-based antral PV isolation underwent a surgical maze procedure. Full-thickness surgical biopsy specimens were obtained from the PV antrum in areas of visible endocardial scar. Before biopsy, intraoperative epicardial electrophysiological recordings were taken from each PV using a circular mapping catheter. Twenty-two PVs were biopsied from the 12 patients 8 ± 11 months after ablation. Eleven of the 22 specimens (50%) revealed transmural scar, and 11 (50%) showed viable myocardium with or without scar. Each biopsy specimen demonstrated evidence of injury, most commonly endocardial thickening (n = 21 [95%]) and fibrous scar (n = 18 [82%]). Seven of the 22 specimens (32%) showed conduction block at surgery. Transmural scar was more likely to be seen in the biopsy specimens from the PVs with conduction block than in specimens from the PVs showing reconnection. However, viable myocardium alone or mixed with scar was seen in 2 specimens from PVs with conduction block. PVs showing electrical reconnection after catheter-based antral ablation frequently reveal anatomic gaps or nontransmural lesions at the sites of catheter ablation. Nontransmural lesions are noted in some PVs with persistent conduction block, suggesting that lesion geometry may influence PV conduction. The histological findings show that nontransmural ablation can produce a dynamic cellular substrate with features of reversible injury. Delayed recovery from injury may explain late recurrences of AF after PV isolation.

Chronic intestinal pseudo-obstruction in a dog: case report

Intestinal pseudo-obstruction is a rare disorder that affects gastrointestinal propulsion. It may be secondary to several pathological conditions or it may develop without a known cause. A 1.2 year-old intact Pug bitch had a history of vomiting and constipation, which were followed by diarrhea and distended abdomen. Hypomotility and dilation of the small intestine, which was filled with gas, were observed during laparotomy. Histologically, full thickness biopsy specimens demonstrated a severe loss and degeneration of leiomyocytes in the inner and outer muscular layers of the intestinal wall, whereas there was a marked hypertrophy and hyperplasia of smooth muscle cells in the lamina propria, and extremely thickened muscularis mucosae arranged in bundles oriented in different directions with marked hypertrophy and hyperplasia of leiomyocytes. Distribution of leiomyocytes was further characterized by immunohistochemistry. These findings support the diagnosis of intestinal pseudo-obstruction in a Pug, associated with degeneration and loss of leiomyocytes in the muscular layer.

Induction of Dermal Collagenesis, Angiogenesis, and Adipogenesis in Human Skin by Injection of Platelet-Rich Fibrin Matrix

To evaluate the histological changes induced in human skin by injection of autologous platelet-rich fibrin matrix (PRFM). Four healthy adult volunteers were included in the study. Platelet-rich fibrin matrix was prepared from 9 mL of autologous blood using a proprietary system (Selphyl; Aesthetic Factors, Wayne, New Jersey) and injected into the deep dermis and immediate subdermis of the upper arms of subjects. Full-thickness skin biopsy specimens were taken from the treated areas over a 10-week period, and the specimens were processed for histological evaluation. Findings from histological examination supported the clinical observation of soft-tissue augmentation. As early as 7 days after treatment, activated fibroblasts and new collagen deposition were noted and continued to be evident throughout the course of the study. Development of new blood vessels was noted by 19 days; also at this time, intradermal collections of adipocytes and stimulation of subdermal adipocytes were noted. These findings became more pronounced over the duration of the study, although the fibroblastic response became much less pronounced. No abnormal mitotic figures were observed at any point, and a very mild chronic inflammatory response was noted only at the earliest time points of the study. Injection of PRFM into the deep dermis and subdermis of the skin stimulates a number of cellular changes that can be harnessed for use. Coupled with prior in vitro and in vivo studies, we now have a much clearer picture of the cellular effects of PRFM and its potential uses in facial plastic surgery. Further work is planned to more clearly elucidate the potential role of PRFM in aesthetic and reconstructive surgery.

Involutional Ectropion and Entropion: Clinicopathologic Correlation Between Horizontal Eyelid Laxity and Eyelid Extracellular Matrix

To investigate the clinicopathologic correlation between horizontal eyelid laxity and extracellular matrix components, such as collagen and elastic fibers, in involutional ectropion and entropion. Another goal was to compare the differences between involutional ectropion and entropion in regard to extracellular matrix content using computer-assisted morphometry. This clinicopathologic study included 20 consecutive patients with involutional ectropion (group 1) and 20 consecutive patients with involutional entropion (group 2). The pinch test was performed to measure horizontal eyelid laxity in both groups. Full-thickness eyelid biopsy specimens were examined by light microscopy and computer-assisted morphometry. The Mann-Whitney U test, the Pearson chi-square test, the Pearson correlation coefficient calculation, and a linear regression analysis were performed. All sections of specimens from patients in groups 1 and 2 revealed abnormal collagen and elastic fibers. The Pearson correlation coefficient revealed a significant negative correlation between horizontal eyelid laxity and extracellular matrix content in the eyelid skin, the pretarsal orbicularis oculi muscle, the perimeibomian tarsal stroma, and the intermeibomian tarsal stroma. Linear regression demonstrated that horizontal eyelid laxity is dependent upon extracellular matrix components in all eyelid regions. Collagen fiber content was significantly increased in specimens from patients in group 1 compared with specimens from patients in group 2. The present findings suggest that a reduction of collagen and elastic fibers may contribute to the development of excessive horizontal eyelid laxity in patients with involutional ectropion and entropion of the lower eyelid.

Colonic endoscopic full-thickness biopsies: from the neuropathological analysis of the myenteric plexus to the functional study of neuromuscular transmission

Better understanding of the pathophysiological mechanisms involved in severe dysmotility disorders is crucial to improve patient management and identify novel therapeutic targets. Recent studies suggested that endoscopic full-thickness biopsies (eFTBs) could be developed as an alternative to surgical biopsies. However, currently it remains unknown whether eFTBs would allow myenteric plexus analysis on whole mounts and the evaluation of neuromuscular transmission. To determine with eFTB specimens the ability to analyze on whole mounts the key parameters of the myenteric plexus, ie, ganglia and neurons, and to perform functional evaluation of neuromuscular transmission. An experimental pilot study in 6 pigs was conducted in accordance with French institutional guidelines. Under general anesthesia, pigs underwent a rectosigmoidoscopy. In each pig, an eFTB was performed at 25, 30, and 35 cm from the anal margin with an EMR-based technique. Tissue specimens were immediately processed for immunohistochemical and/or functional ex vivo analysis of neuromuscular transmission. In 2 pigs, over-the-scope clips were used to seal the perforation. Feasibility of obtaining specimens containing myenteric plexus and muscularis propria, quantitative and standardized immunohistochemical evaluation of ganglia and myenteric neurons, ex vivo assessment of neuromuscular transmission and its pharmacology, and closure rate (ancillary study). Adequate tissue specimens were obtained in 100% of the procedures, on average, in 6±2 minutes. Immunohistochemical analysis of a whole mount of the myenteric plexus showed that each eFTB contained 14±5 ganglia and 1562±1066 myenteric neurons. In circular muscle strips, electrical field stimulation or exposure to a pharmacological agent induced a specific tissue response. A successful closure was achieved in 50% of cases. Nonsurvival study; safety of the procedure needs to be specifically assessed and compared with recently published data. We demonstrate, for the first time, that full-thickness biopsy specimens obtained by using an endoscopic approach allow the performance of a precise study of the ENS phenotype on whole mounts of the myenteric plexus and the performance of functional studies such as evaluation of neuromuscular transmission. However, further studies are warranted to identify the optimal and safest endoscopic procedure before application of eFTB in humans.

Colonic Endoscopic Full-Thickness Biopsies: From the Neuropathological Analysis of the Myenteric Plexus to the Functional Study of Neuromuscular Transmission

Background Better understanding of the pathophysiological mechanisms involved in severe dysmotility disorders is crucial to improve patient management and identify novel therapeutic targets. Recent studies suggested that endoscopic full-thickness biopsies (eFTBs) could be developed as an alternative to surgical biopsies. However, currently it remains unknown whether eFTBs would allow myenteric plexus analysis on whole mounts and the evaluation of neuromuscular transmission. Objective To determine with eFTB specimens the ability to analyze on whole mounts the key parameters of the myenteric plexus, ie, ganglia and neurons, and to perform functional evaluation of neuromuscular transmission. Design An experimental pilot study in 6 pigs was conducted in accordance with French institutional guidelines. Intervention Under general anesthesia, pigs underwent a rectosigmoidoscopy. In each pig, an eFTB was performed at 25, 30, and 35 cm from the anal margin with an EMR-based technique. Tissue specimens were immediately processed for immunohistochemical and/or functional ex vivo analysis of neuromuscular transmission. In 2 pigs, over-the-scope clips were used to seal the perforation. Main Outcome Measurements Feasibility of obtaining specimens containing myenteric plexus and muscularis propria, quantitative and standardized immunohistochemical evaluation of ganglia and myenteric neurons, ex vivo assessment of neuromuscular transmission and its pharmacology, and closure rate (ancillary study). Results Adequate tissue specimens were obtained in 100% of the procedures, on average, in 6 ± 2 minutes. Immunohistochemical analysis of a whole mount of the myenteric plexus showed that each eFTB contained 14 ± 5 ganglia and 1562 ± 1066 myenteric neurons. In circular muscle strips, electrical field stimulation or exposure to a pharmacological agent induced a specific tissue response. A successful closure was achieved in 50% of cases. Limitations Nonsurvival study; safety of the procedure needs to be specifically assessed and compared with recently published data. Conclusions We demonstrate, for the first time, that full-thickness biopsy specimens obtained by using an endoscopic approach allow the performance of a precise study of the ENS phenotype on whole mounts of the myenteric plexus and the performance of functional studies such as evaluation of neuromuscular transmission. However, further studies are warranted to identify the optimal and safest endoscopic procedure before application of eFTB in humans.