Normal Histological Appearance Research Articles

Disaccharidase Activity in Infants and Comparison Based on Symptoms and Histological Changes

There is uncertainty regarding disaccharidase activity (DA) in infants. In this study, values for DA in infants were established and compared with symptoms and intestinal mucosal histological appearance. Disaccharidase activity and histological appearance of endoscopically obtained intestinal mucosal biopsy specimens from 131 infants (75 males; mean age 180 days; range 20-364 days) obtained during an 8-year period were reviewed. Patients were divided into 2 groups on the basis of absence (group 1; n = 56) or presence (group 2; n = 75) of failure to thrive (FTT) and/or diarrhea. These groups were subdivided into 3 subgroups on the basis of histological findings: normal histological appearance (A), mild histological abnormalities (B), and moderate to severe histological abnormalities (C). The DA from patients in group 1A represent values in infants who were free of diarrhea/FTT and who had normal intestinal mucosal histological appearance. The geometric means (95% CI) in units of DA were as follows: lactase 33.7 (normal range 29.0-39.1), sucrase 48.9 (normal range 44.2-54.1), maltase 160.5 (normal range 144.4-178.3), and palatinase 11.2 (normal range 9.7-12.9). Differences in DA were not related to symptoms, in the absence of histological abnormalities (1A vs 2A), but rather on the presence of histological abnormalities even in the absence of symptoms (1A vs 1B). Differences were also found when patients with FTT and/or diarrhea with abnormal histological appearance (2B and 2C) were compared with patients with no FTT and/or diarrhea with a normal brush border (1A). We outline DA values in a large cohort of infants. DA in infants, as in children, relates to intestinal mucosal histological appearance rather than to symptoms.

INTESTINAL ISCHEMIA-REPERFUSION-INDUCED ACUTE LUNG INJURY AND ONCOTIC CELL DEATH IN MULTIPLE ORGANS

Most acute respiratory distress syndrome studies have been focused on the lung injury. Little is known about other organs during the development of acute respiratory distress syndrome. Herein, we investigated the injury and cell death in multiple organs after intestinal ischemia-reperfusion (IIR) in C57BL/6 mice. Terminal transferase dUTP nick end labeling staining was used as a marker of cell death. Caspase 3 and cathepsin B activation as markers of caspase-dependent and caspase-independent apoptosis, respectively, and electron microscopy for ultimate characterization of cell death were used. In comparison with control and sham-operated mice, the IIR group showed interstitial inflammatory infiltrates in the lung and significant increases of lung injury parameters and plasma lactate dehydrogenase and aspartate aminotransferase levels. Terminal transferase dUTP nick end labeling-positive cells and immunostaining for hemeoxygenase 1, an enzyme induced by inflammatory stimuli, were increased in the lung, heart, and kidney, but not in the liver. The number of hemeoxygenase 1-positive cells positively and significantly correlated to the number of terminal transferase dUTP nick end labeling-positive cells. Cell death was not associated with caspase 3 or cathepsin B activation. Electron microscopy showed morphological features compatible with oncotic rather than apoptotic cell death or necrosis, including mitochondrial swelling and cytoplasm disorganization in pulmonary and renal epithelial cells, lung and cardiac endothelial cells, and myocytes. These results indicate that, although lung injury is the most significant manifestation after IIR, oncotic cell death occurs in the lung, heart, and kidney, which may be related to ischemia and inflammation.

BMP-14 Gene Therapy Increases Tendon Tensile Strength in a Rat Model of Achilles Tendon Injury

Molecular and cellular-based enhancements of healing combined with conventional methods may yield better outcomes after the surgical management of tendon injury. We examined the histological and biomechanical effects of adenovirus-mediated transgene expression of bone morphogenetic protein-14 (BMP-14) on healing in a rat Achilles tendon laceration model. Specifically, we hypothesized that this delivery system for gene therapy would hasten the restoration of the normal histological appearance and tensile strength of a surgically repaired tendon. The right Achilles tendon of ninety male Sprague-Dawley rats was transected, repaired, and immediately infected with adenovirus expressing either the gene for green fluorescent protein (AdGFP) or the gene for human BMP-14 and green fluorescent protein (AdBMP-14). A sham control group received no viral-mediated infection after repair. Animals from each of the three groups were killed at one, two, and three weeks after surgery. The retrieved tendons were inspected, examined under light and fluorescent microscopy, and tested to determine their tensile strength. Tendons transduced with BMP-14 exhibited less visible gapping, a greater number of neotenocytes at the site of healing, and 70% greater tensile strength than did either those transduced with GFP or the sham controls at two weeks after repair. Histological examination revealed no inflammatory response to the adenovirus in tendons transduced with BMP-14 or GFP. No ectopic bone or cartilage formed in the tendons transduced with BMP-14. Adenovirus-mediated gene therapy with BMP-14 expedites tendon-healing in this animal model. No adverse immunological response to the adenoviral vector was detected in the host tissue, and the local production of BMP-14 did not induce unwelcome bone or cartilage formation within the healing tendon. The results of this animal study suggest that gene therapy with BMPs may improve the capacity of injured musculoskeletal tissue to heal.

A Mouse Model of Orthotopic Vascularized Aerated Lung Transplantation

Outcomes after lung transplantation are markedly inferior to those after other solid organ transplants. A better understanding of cellular and molecular mechanisms contributing to lung graft injury will be critical to improve outcomes. Advances in this field have been hampered by the lack of a mouse model of lung transplantation. Here, we report a mouse model of vascularized aerated single lung transplantation utilizing cuff techniques. We show that syngeneic grafts have normal histological appearance with minimal infiltration of T lymphocytes. Allogeneic grafts show acute cellular rejection with infiltration of T lymphocytes and recipient-type antigen presenting cells. Our data show that we have developed a physiological model of lung transplantation in the mouse, which provides ample opportunity for the study of nonimmune and immune mechanisms that contribute to lung allograft injury.

Transgenic Male Mice Expressing Human Hydroxysteroid Dehydrogenase 2 Indicate a Role for the Enzyme Independent of Its Action on Sex Steroids

Hydroxysteroid (17beta) dehydrogenase 2 (HSD17B2) has been shown to inactivate both estrogens and androgens and activate 20alpha-hydroxyprogesterone to progesterone. In the present study, we generated transgenic (TG) mice ubiquitously expressing human HSD17B2. The TG mice produced showed growth retardation and delayed eye opening at the postnatal age. Disrupted spermatogenesis was evident in the presence of normal serum and intratesticular testosterone, progesterone, and normal circulating LH concentrations. A proper androgen action in the target tissues was confirmed by normal histological appearance of the prostate and epididymis. Furthermore, quantitative RT-PCR analysis indicated only a slight decrease in androgen-dependent gene expression in the prostate. The disrupted spermatogenesis was not associated with increased germ cell apoptosis as analyzed by caspase-3 activation. However, it resulted in infertility in the HSD17B2 TG males after the age of 3 months, and at the age of 6 months the seminiferous tubules showed a Sertoli cell-only phenotype. The data indicate that the growth retardation and disrupted spermatogenesis are not due to a lack of proper estrogen or androgen action. Interestingly, the testicular phenotype and some of the other phenotypic changes described are typically observed in mice with reduced action of retinoic acid signaling. This, together with the rescue of the testis phenotype by a synthetic retinoic acid receptor agonist (4-[(E)-2-(5, 6, 7, 8-tetrahydro-5, 5, 8, 8-tetramethyl-2-naphthalenyl)-1-propenyl] benzoic acid), suggests a role for HSD17B2 in the action of retinoids, in addition to its oxidative HSD17B activity on sex steroids.

An approach to the paediatric renal biopsy

Although the principles the pathologist uses to assess renal biopsies are similar when reporting adult and paediatric biopsies, the interpretation of the findings may differ owing to relative differences in the frequencies of particular diagnoses in childhood versus adulthood, as well as age-related changes in normal histological appearances. In addition, there are a range of conditions that are either unique to or much more frequent in childhood compared with adult practice, for example congenital nephrotic syndrome subtypes, whereas other conditions, such as hypertensive renal disease or diabetic nephropathy, remain a significant component of adult renal pathology practise but are almost never encountered in childhood. The renal biopsy plays a central role in the management of many paediatric conditions presenting to the nephrologist, and percutaneous ultrasound-guided renal biopsy in children appears safe, with a low frequency (<1%) of serious complications. The most common indication for renal biopsy in childhood is nephrotic syndrome, either in the first year of life, in which the differential diagnoses are usually relatively specific to this age group, or in later childhood, when the major differential diagnoses are minimal-change nephropathy (minimal-change disease) and focal segmental glomerulosclerosis. Other entities that may be encountered commonly in paediatric renal biopsy practise include congenital disorders of the glomerular capillary basement membrane, such as Alport nephropathy, and a range of cystic diseases of the kidney. This review will provide an overview of these issues, focusing predominantly on those issues and entities specific to paediatric practise.

Evaluation of a Burdizzo Castrator for Neutering of Dogs

A Burdizzo castrator was evaluated for the neutering of dogs. Histological and morphological changes of spermatic cells and peripheral serum testosterone after challenge with a GnRH-analogue (gonadorelin) were assessed. There was a control group (G1), a surgically castrated group (G2) and a Burdizzo group (G3) divided in two, G3a receiving two crunches in each spermatic cord and G3b receiving one crunch in each spermatic cord. Sixteen days after application of the Burdizzo blood samples were taken from the dogs at 30 min interval during 2 h; after the second sample the dogs were treated with 1 mug/kg body weight of gonadorelin i.v. The same protocol of gonadorelin challenge was performed in G1 and G2 dogs. The G2 dogs were surgically castrated after the second blood sample, before the gonadorelin treatment, and the G1 dogs after the last blood sample. The excised gonads were examined histologically, and sperm smears were prepared from the caudae epididymidis. The testes and plexus pampiniformis of the G1 and G2 dogs had a normal histological appearance, and they had morphologically normal epididymal sperm cells. In all G3 dogs, there was an acute fibrosis with an inflammatory reaction in the plexus pampiniformis. The testes from the G3a dogs showed diffuse areas of infarction and degeneration of the parenchyma. Similar but less diffuse lesions were seen in group 3b dogs. The deferent ducts from all G3 dogs showed vasitis and/or sperm granulomas. Azoospermia or sperm malformations were observed in the epididymal smears from the G3 dogs. Testosterone concentration in the G1 dogs increased after gonadorelin application (p < 0.0001). The G2 dogs had basal testosterone levels after castration (p < 0.001) and did not respond to gonadorelin. Groups 3a and b showed a slight but non-significant increase in testosterone concentration after gonadorelin challenge, supposedly due to the reduction of testicular blood flow and loss of testicular interstitial tissue.

Restoration of elbow flexion by performing contralateral lateral thoracic and thoracodorsal nerve transfers after experimental musculocutaneous nerve transection

The immediate transfer of the right lateral thoracic nerve (LTN) and the thoracodorsal nerve (TDN) to the transected left musculocutaneous nerve (MCN), leading to nerve cross-neurotization, was performed in cats to evaluate reinnervation of the biceps brachii muscle (BBM). Surgery to produce cross-neurotization of the MCN was performed in 12 cats (treatment group). Transection of the MCN was performed without attempts at neurotization in three cats (control group). Reinnervation of the BBM was assessed by performing electromyography (EMG) 6 months (14 cats) and 26 months (one cat) postsurgery. True Blue retrograde axonal tracing studies, tensile force measurements (muscle extensometry), and histopathological analyses were performed. All cats in the treatment group recovered voluntary contraction of the BBM and regained elbow flexion. Electromyography revealed no abnormal spontaneous activity in the BBM. Muscle evoked potentials were recorded in that muscle after right C-8 ventral branch stimulation. The muscle contraction strength in the left BBM varied from 108 to 557 g. The BBMs regained their normal appearances. The region of the MCN distal to the anastomosis displayed a normal histological appearance. Fluorescence was detected in the ventral horn of the spinal cord in the right C-8 and T-1 segments. In contrast, in all cats in the control group there was atrophy of the BBM, no EMG signal, and no clinical sign of recovery. There was no contraction of the BBM, no labeled neuron in the spinal cord, and the MCN displayed major degenerative changes. These findings demonstrate that the LTN and TDN can be used to neurotize injured contralateral brachial plexus nerves and obtain successful reinnervation in cats.

Antagonism of Epidermal Growth Factor Receptor Tyrosine Kinase Ameliorates the Psoriatic Phenotype in Organ-Cultured Skin

Psoriatic plaque skin incubated for eight days in organ culture in the presence of a potent epidermal growth factor (EGF) receptor tyrosine kinase (RTK) antagonist reverted to a more normal histological appearance, while untreated psoriatic plaque skin retained histological features associated with the psoriatic phenotype. In concomitant studies it was shown that the EGF-RTK antagonist had no significant effect on histological features of non-psoriatic skin and no effect on dermal function, i.e. elaboration of both type I procollagen and matrix metalloproteinase-1 (MMP-1; interstitial collagenase). When human epidermal keratinocytes were treated with the EGF-RTK antagonist in monolayer culture, growth inhibition was seen (ED₅₀ = approximately 0.06 µM). When dermal fibroblasts were exposed to the EGF-RTK antagonist in monolayer culture, proliferation, MMP-1 and type I procollagen production were essentially unaffected at concentrations which interfered with keratinocyte growth (up to 1 µM). The capacity of the EGF-RTK antagonist to modulate the histological features of psoriatic skin in organ culture under conditions in which normal skin architecture and dermal function are largely unaffected suggests a potential for anti-psoriatic therapy.

Immunohistochemical expression of DNA mismatch repair (MMR) system proteins (hMLH1, hMSH2) in cervical preinvasive and invasive lesions

The purpose of our study was to analyze the immunohistochemical expression of two MMR system proteins at different steps of neoplastic progression within the squamous cervical epithelium. We compared cases showing normal histologic appearance with those affected by low and high-grade squamous intraepithelial lesions and invasive cervical carcinoma. We investigated formalin-fixed and paraffin-embedded tissue specimens obtained from 83 selected patients (55 with preinvasive neoplastic lesions and 28 with invasive squamous cervical carcinoma) for the expression of hMSH2 and hMLH1 at the immunohistochemical level. We also included 30 patients with histologically normal cervix as a control group. Epithelial cells of CIN lesions showed a significant increase in the expression of both hMLH1 and hMSH2 proteins compared to non-neoplastic squamous epithelium ( p < 0.0001 ). The cases of invasive carcinoma showed a positivity for hMLH1 protein that was statistically lower than that for non-neoplastic cells ( p = 0.0009 ) and that for cases with CIN ( p < 0.0001 ). Positivity for hMSH2 protein was higher than that for normal epithelium ( p = 0.0007 ), but lower than that for preinvasive lesions ( p = 0.0001 ). Preinvasive lesions showed increased expression of both proteins if compared with normal esocervical epithelium. Neoplastic stromal invasiveness is associated with a significant loss of hMLH1 function.

A long-term serial histological evaluation of the patellar tendon in humans after harvesting its central third

It is previously known that the patellar tendon does not normalise histologically in the short term after harvesting its central third. The aim of the study was to obtain long-term serial biopsies from the central and peripheral parts of the patellar tendon after the harvesting procedure. Our hypothesis was that in the long term after harvesting its central third, the patellar tendon does not regain normal histological appearance. Seventeen consecutive patients, who had undergone anterior cruciate ligament reconstruction using patellar tendon autografts, were included. Percutaneous biopsies were obtained under ultrasonographic guidance 27 (24-29) months and 71 (68-73) months after the index procedure, respectively. The sections were stained with haematoxylin and eosin. The biopsies were evaluated using light microscope. Both at 27 months and 71 months, the fibre structure was deteriorated and the vascularity and cellularity were increased compared with normal tendon. This was seen in both the central and peripheral parts of the tendon. In conclusion, nearly 6 years after harvesting its central third, the patellar tendon had still not normalised histologically, neither in the central nor peripheral parts of the tendon.

Hypoglycemic effect of Du-zhong ( Eucommia ulmoides Oliv.) leaves in streptozotocin-induced diabetic rats

The current study investigated whether Du-zhong ( Eucommia ulmoides Oliv.) leaves could improve the hyperglycemia in streptozotocin (STZ)-induced diabetic rats. Male Sprague–Dawley rats were divided into a non-diabetic group (NDM), diabetic group (DM), diabetic group supplemented with powdered Du-zhong leaves (DM–PDZ) and diabetic group supplemented with a water extract of the powdered Du-zhong leaves (DM–WDZ). Diabetes was induced by injecting STZ (70 mg/kg B.W., i.p.). The powdered Du-zhong leaves or its powdered water extract was add to a standard diet based on 1% dried Du-zhong leaves (1 g PDZ/100 g diet and 0.187 g WDZ/100 g diet, respectively) for 3 weeks. Body weight was significantly higher in both types of Du-zhong leaves supplemented groups than in the DM group. The blood glucose levels were significantly lower in the DM–PDZ and DM–WDZ groups than in the DM group (20.05 ± 0.88 and 18.96 ± 1.23 mmol/l versus 24.42 ± 1.07 mmol/l, P < 0.05), whereas the plasma insulin and C-peptide levels were significantly higher in the PDZ and WDZ supplemented groups than in the DM group (7.45 ± 0.27 and 7.62 ± 0.69 μl U/ml versus 3.75 ± 0.27 μl U/ml for the plasma insulin, and 224.52±14.6 and 239.76 ± 15.52 pmol/l versus 166.5 ± 10.4 pmol/l for the plasma C-peptide, respectively, P < 0.05). The supplementation of PDZ and WDZ also resulted in lower plasma urea nitrogen levels compared to the DM group. Du-zhong leaves supplement seemed to be helpful to preserve the normal histological appearance of pancreatic islets as well as to preserve insulin-positive β-cells but it did not reverse the effect of STZ to a great extent. Accordingly, the reduction in plasma glucose by the powdered Du-zhong leaves and its water extract is quite small but significant, nevertheless, this was occurred with simultaneous the increase in plasma insulin and C-peptide. They improved hyperglycemia and seemingly enhance the function of pancreatic β-cells in STZ-induced diabetic rats.

Spermatogenesis following syngeneic testicular transplantation in Balb/c mice.

Transplantation of spermatogonial stem cells in cross-species has been widely used to study the function of Sertoli cells and the effect of phylogenetic distance between donor and recipient animals on the outcome of spermatogonial transplantation, whereas there have been only a few reports on the transplantation of testis tissue. The objective of the present study was to examine the development of grafted testes and the kinetics of spermatogenesis following syngeneic testicular transplantation in both male and female recipient Balb/c mice in an effort to establish an in vivo culture system and to compare the effects of host sex on spermatogenesis. The testes from 5-day-old Balb/c mice were transplanted under the dorsal skin of four-week-old mice. Twenty male and twenty female Balb/c mice were used as the hosts and each host received 4 grafts. The recipient mice were killed at 1, 2, 3, 5, 7, 9, 12 and 15 weeks after transplantation. The graft survival rate and graft size were measured. The status of spermatogenesis was assessed by histological analyses. The expression of the spermatid-specific Protamine-2 gene was examined by RT-PCR. Overall, 70.3% of the testicular grafts in male hosts and 67.2% in female hosts survived. All recovered grafts had increased in volume, some of them had increased by more than 30-fold. The architecture of the seminiferous tubules in female hosts appeared to be better than that in male hosts. The round spermatids were the most advanced germ cells until 15 weeks after transplantation, and no complete spermatozoon was observed in any of the grafts. The expression of protamine-2 was detected in grafts from 5 weeks posttransplantation in both male and female hosts, confirming that the spermatogenic cells differentiated into spermatids. In contrast to grafts, the testes of male hosts had a normal histological appearance. The results showed the schedule of spermatogenesis following syngeneic testicular transplantation in both male and female hosts. This model could be useful for further studies involving the endocrinology of the testis and the mechanisms of spermatogenesis.

P‐88 Endocrine dermatosis and granulosa cell tumour in a red panda

A 9‐year‐old red panda from the Vienna Zoo showed progressive hair loss of 2 years duration beginning at the tip of the tail and slowly spreading to the lower back, abdomen and thorax. Severe pruritus and mild automutilation was present only at the tail. Antifungal and antibiotic therapy showed little effect. Skin biopsies showed a thin hyperkeratotic epidermis, moderate superficial dermal sclerosis, mild superficial pyoderma, and complete atrophy of hair follicles and adnexae. Ultrasonography revealed an anechogenic circular mass 3 cm in diameter limited by echogenic trabeculae. The animal was euthanized. Necropsy revealed two smooth red‐brown soft solid nodules (3×3×2 cm) situated bilaterally at the caudal pole of the kidneys. Viscera, thyroid and adrenal glands as well as the uterus showed normal macroscopic and histologic appearance. Histologically, the pararenal nodules were recognized as enlarged ovaries with a small number of follicles and a large solid mass of slightly atypical vacuolated polygonal cells of Leydig‐cell character, which partly invaded the adjacent adipose tissue and were accompanied by discrete and strongly vascular stroma. Diagnosis of bilateral granulosa cell tumour was made. We concluded that the progressive hypotrichotic dermatosis was due to an endocrine abnormality. Funding: Self‐funded.

Transplantation of the Autologous Submandibular Gland to the Lacrimal Basin in Rats

Purpose: In this study, we designed an animal experiment in which we transferred a part of the autologous submandibular gland without performing a microvascular anastomosis. We studied histological changes and functional effects in the transfer glands. Method: Thirty male adult Sprague-Dawley rats were divided into three groups. In each animal of the three groups, the right eye was the control eye and the left eye the experimental eye. Surgical removal of the extraorbital lacrimal gland from the control eyes was performed to create a condition simulating keratoconjunctivitis sicca. In the experimental eyes of group 1, in addition to the removal of the extraorbital lacrimal gland, a part of the autologous submandibular gland was transferred to the orbit and fixed to the intraorbital lacrimal gland. In the experimental eyes of group 2, in addition to the removal of the extraorbital lacrimal gland, an aseptic silicon rubber was transferred to the orbit and fixed to the intraorbital lacrimal gland. In the experimental eyes of group 3, there was no removal of the extraorbital lacrimal gland but instead a sham operation was performed. The histological changes and innervation pattern in the transferred submandibular gland of group 1 were observed. Tear secretion of each group was measured to study the functional effect. Results: Three months after the transplantation, the transferred submandibular glands were similar to the unoperated submandibular glands both in histology and innervation pattern. In group 1, the tear secretion in the experimental eyes was significantly greater than that of the control eyes at 2 and 3 months following transfer. In group 2, no significant difference was noted between the experimental eyes and control eyes. In group 3, the difference in tear secretion between the experimental eyes and control eyes was significant. Conclusion: The result of this study revealed that although the procedure did not involve vascular anastomosis, the transfer gland showed a normal histological appearance and good reinnervation, even 3 months after the transfer. These transferred submandibular glands continued to secrete tears. This secretion continued to increase up until the end of the experimental period.

Local ex vivo gene therapy with bone marrow stromal cells expressing human BMP4 promotes endosteal bone formation in mice.

Bone loss in osteoporosis is caused by an imbalance between resorption and formation on endosteal surfaces of trabecular and cortical bone. We investigated the feasibility of increasing endosteal bone formation in mice by ex vivo gene therapy with bone marrow stromal cells (MSCs) transduced with a MLV-based retroviral vector to express human bone morphogenetic protein 4 (BMP4). We assessed two approaches for administering transduced MSCs. beta-Galactosidase (beta-Gal) transduced C57BL/6J mouse MSCs were injected intravenously via tail vein or directly injected into the femoral bone marrow cavity of non-marrow-ablated syngenic recipient mice and bone marrow cavity engraftment was assessed. BMP4- or beta-Gal-transduced cells were injected into the femoral bone marrow cavity and effects on bone were evaluated by X-ray, peripheral quantitative computed tomography (pQCT), and histology. After tail-vein injection less than 20% of recipient mice contained beta-Gal-positive donor cells in femur, humerus or vertebra marrow cavities combined, and in these mice only 0.02-0.29% of injected cells were present in the bone marrow. In contrast, direct intramedullary injection was always successful and an average of 2% of injected cells were present in the injected femur marrow cavity 24 hours after injection. Numbers of donor cells decreased over the next 14 days. Intramedullary injection of BMP4-transduced MSCs induced bone formation. Trabecular bone mineral density (BMD) determined by pQCT increased 20.5% at 14 days and total BMD increased 6.5% at 14 days and 10.4% at 56 days. The present findings support the feasibility of using ex vivo MSC-based retroviral gene therapy to induce relatively sustained new bone formation, with normal histological appearance, at endosteal bone sites.

Apoptotic neuronal death following deep hypothermic circulatory arrest in piglets.

Deep hypothermic circulatory arrest (DHCA), as used in infant heart surgery, carries a risk of brain injury. In a piglet DHCA model, neocortical neurons appear to undergo apoptotic death. Caspases, cytochrome c, tumor necrosis factor (TNF), and Fas play a role in apoptosis in many ischemic models. This study examined the expression of these factors in a DHCA piglet model. Thirty-nine anesthetized piglets were studied. After cardiopulmonary bypass (CPB) cooling of the brain temperature to 19 degrees C, DHCA was induced for 90 min, followed by CPB rewarming. After separation from CPB, piglets were killed at 1, 4, 8, 24, and 72 h and 1 week. Caspase-8 and -3 activity, and concentrations of TNF-alpha, Fas, Fas-ligand, cytochrome c, and adenosine triphosphate (ATP) were measured in the neocortex by enzymatic assay and Western blot analysis. Caspase-8 and -3 activity and cell death were examined histologically. Significance was set at P < 0.05. In neocortex, damaged neurons were not observed in control (no CPB), rarely observed in CPB (no DHCA), and rarely observed in the DHCA 1-h, 4-h, and 1-week reperfusion groups. However, they were seen frequently in the DHCA 8-, 24-, and 72-h reperfusion groups. Although neuronal death was widespread 8-72 h after DHCA, cortical ATP concentrations remained unchanged from control. Both caspase-3 and -8 activities were significantly increased at 8 h after DHCA, and caspase-3 concentration remained elevated for as long as 72 h. Caspase-3 and -8 activity was also observed in damaged neocortical neurons. Cytosolic cytochrome c and Fas were significantly expressed at 1 h and 4 h after DHCA, respectively. Fas-ligand and TNF-alpha were not observed in any group. After DHCA, induction of apoptosis in the neocortex occurs within a few hours of reperfusion and continues for several days. Increased Fas, cytochrome c, and caspase concentrations, coupled with normal brain ATP concentrations and apoptotic histologic appearance, are consistent with the occurrence of apoptotic cell death.

Human intestinal spirochetosis

Whenever biopsy material obtained from endoscopically normal colorectal mucosa reveals the blue haematoxyphilic line between the microvilli of the covering epithelium, the rare condition of intestinal spirochetosis is diagnosed. The classification of the bacteria detected with the aid of special stains (e.g. the Warthin Starry silver stain) and in the electron microscope, continues to be something of a problem. A further point of contention is the question whether this spirochetal infection is of pathological significance or not. A point mitigating against pathogenicity is the fact that no histological signs of an inflammatory reaction are to be seen. Also, the symptoms of patients with intestinal spirochetosis are such that they provide no basis for a pronouncement on whether the infection is of a pathological or a pathological nature. On the other hand, however, a number of studies do seem to indicate that the spirochetes might be the cause of such symptoms as diarrhoea, constipation and abdominal pain. A point that would appear to support this view is the fact that such symptoms may disappear after successful treatment with metronidazole. The histological diagnosis is easily established when, faced by an apparently normal histological appearance of the colorectal mucosa, the pathologist considers the possibility of spirochetosis, and undertakes a specific search for the blue haematoxyphilic line in the covering epithelium of the colorectal mucosa.

Tensile strength of the supraspinatus after reimplantation into a bony trough: An experimental study in rabbits

The goals of this study were to determine the strength of the supraspinatus tendon after reimplantation into a bony trough and to find out whether the fibrocartilaginous enthesis reformed. In 21 rabbits, the supraspinatus tendon was transected and reinserted into a bony trough at the greater tuberosity. After sacrifice at 8 and 12 weeks, tensile strength was measured. Microscopically, the presence of fibrocartilage and the spatial orientation of the cartilage columns and collagen fibers were assessed. At sacrifice, 14 of 21 reinserted specimens had healed successfully and were studied. Most mechanical failures occurred through bone, and none failed at the site of reimplantation. The mean peak loads of the operated tendons were significantly lower than their controls (8 weeks, 134.8 ± 49.9 N vs 223.1 ± 33.4 N, and 12 weeks, 172.2 ± 68.2 N vs 274.1 ± 70.0; P =.013 and P =.025, respectively). Histologically, at 8 weeks, the fibrocartilaginous enthesis had partially reformed; it was narrower than normal, and the collagen fibers had only partially assumed their normal spatial arrangement. Twelve weeks after reimplantation, 4 of 7 entheses had a normal histologic appearance. We conclude that return of strength of the supraspinatus tendon is evident 8 weeks after surgical reattachment into a bony trough and that the fibrocartilaginous enthesis is normal in over half of the specimens at 12 weeks. The subchondral bone was weaker than the reinserted tendon. The results support the clinical practice of surgical reimplantation. Avoiding active exercises early while promoting them later could improve the surgical results and reduce the effects of disuse. (J Shoulder Elbow Surg 2002;11:504-9)

Dietary lectins can stimulate pancreatic growth in the rat.

Lectins are proteins or glycoproteins of nonimmune origin, which bind specifically to carbohydrate structures. They are widespread in the human diet, and many are resistant to digestion. High doses of lectins have been shown to stimulate intestinal and pancreatic growth. The aim of the present study was to investigate the long-term actions of low doses of lectins on the rat intestine and pancreas. A long-term carcinogenesis study was performed using low levels (40 micro g/rat/day) of peanut (PNA) or mushroom lectin (ABA) which bind to O-linked (mucin-type) oligosaccharides in the gut. While this was primarily designed as a colon carcinogenesis study, the pancreas was also investigated. No significant changes in colon carcinogenesis were seen, however, the colons were slightly heavier in the lectin treated groups. The weight of the pancreas was significantly greater (by 18 and 23%) in both lectin treated groups (P < 0.03/0.001). The weights of the acini and septal tissue were also increased by 39-46% in PNA and ABA fed animals, respectively (P < 0.002); there was no significant change in the endocrine pancreas. In conclusion, long-term feeding of low doses of lectin can influence pancreatic growth, and this trophic action may have potential adverse implications for the development of pancreatic cancer in humans.