Pathogenicity and oxidative stress in Nile tilapia caused by Aphanomyces laevis and Phoma herbarum isolated from farmed fish

Identified (n = 17) and unidentified (n = 1) fish-pathogenic fungal species from 10 genera of Oomycetes and soil fungi were isolated from 40 infected freshwater fish samples of the species Oreochromis niloticus niloticus (Nile tilapia) and Clarias gariepinus (African catfish). Samples were collected from various fish farms in the Nile Delta, Egypt. Nile tilapia were tested in aquaria for their susceptibility to the commonest Oomycetes species, Aphanomyces laevis and Achlya klebsiana, and also against the 2 most prevalent pathogenic soil fungi, Paecilomyces lilacinus and Phoma herbarum. Two techniques were used: water bath exposure and intramuscular (subcutaneous) injection. Water bath exposure to the 2 species of Oomycetes caused greater mortalities of O. niloticus niloticus than intramuscular injection, but the reverse was true of the soil fungal species. Regardless of the infection method, the 2 Oomycetes species were more potent pathogens than the soil fungal species. In both gills and mytomal muscles of fish infected by A. laevis and P. herbarum, we measured and compared with controls the oxidative stress parameters total peroxide (TP), lipid peroxidation (LPO) and nitric oxide (NO), as well as levels of the antioxidants vitamin E and glutathione (GSH), and superoxide dismutase (SOD) and catalase (CAT) activities. Infection by these 2 fungal species through either spore suspension or spore injection significantly increased oxidative damage in gills and induced marked decrease in most studied antioxidants. In addition, both routes showed similar effects and A. laevis depressed the antioxidants CAT, vitamin E and GSH more than P. herbarum.

Clinical role of anti-granulocyte MoAb versus radiolabeled white blood cells

Scintigraphy with white blood cells (WBC), labeled with ¹¹¹In-oxine or (99m)Tc-hexamethylpropyleneamine oxime (HMPAO), and anti-granulocyte scintigraphy using (99m)Tc-labeled monoclonal antibodies (MoAb), or fragments thereof, are established procedures for the diagnostic workup of infectious or inflammatory disease processes. Clinically severe afflictions such as fever of unknown origin (FUO), infectious joint replacements, osteomyelitis, vascular graft infections or cardiovascular infections often present where noninvasive proof of granulocytic inflammatory activity is more useful than mere morphology-based radiological diagnostic approaches. The labeling differences between WBC and antigranulocyte antibodies produce different pharmacokinetics and patterns of tracer accumulation and distribution. Together with the physical imaging properties of the respective isotope used for imaging, the diagnostic value of a tracer depends on the clinical setting. Thus, despite the easier and safer handling of antibody-based in-vivo labeling, indications for in-vivo labeled WBC remain. As a consequence there is as yet no ideal inflammation tracer, also bearing in mind that neither WBCs nor antibody-diagnostics can reliably differentiate sterile inflammation from infection. Although positron emission tomography (PET) using e.g. FDG-PET is replacing conventional scintigraphies in some indications, both in vivo and in vitro labelled leukocytes will remain an important clinical pillar in the diagnosis of infection and inflammation.

Distinctive response of CNS glial cells in oro-facial pain associated with injury, infection and inflammation

Oro-facial pain following injury and infection is frequently observed in dental clinics. While neuropathic pain evoked by injury associated with nerve lesion has an involvement of glia/immune cells, inflammatory hyperalgesia has an exaggerated sensitization mediated by local and circulating immune mediators. To better understand the contribution of central nervous system (CNS) glial cells in these different pathological conditions, in this study we sought to characterize functional phenotypes of glial cells in response to trigeminal nerve injury (loose ligation of the mental branch), infection (subcutaneous injection of lipopolysaccharide--LPS) and to sterile inflammation (subcutaneous injection of complete Freund's adjuvant--CFA) on the lower lip. Each of the three insults triggered a specific pattern of mechanical allodynia. In parallel with changes in sensory response, CNS glial cells reacted distinctively to the challenges. Following ligation of the mental nerve, both microglia and astrocytes in the trigeminal nuclear complex were highly activated, more prominent in the principal sensory nucleus (Pr5) and subnucleus caudalis (Sp5C) area. Microglial response was initiated early (days 3-14), followed by delayed astrocytes activation (days 7-28). Although the temporal profile of microglial and astrocyte reaction corresponded respectively to the initiation and chronic stage of neuropathic pain, these activated glial cells exhibited a low profile of cytokine expression. Local injection of LPS in the lower lip skin also triggered a microglial reaction in the brain, which started in the circumventricular organs (CVOs) at 5 hours post-injection and diffused progressively into the brain parenchyma at 48 hours. This LPS-induced microglial reaction was accompanied by a robust induction of IκB-α mRNA and pro-inflammatory cytokines within the CVOs. However, LPS induced microglial activation did not specifically occur along the pain signaling pathway. In contrast, CFA injection led to minor microglial morphological changes and an induction of IκB-α mRNA in the CVO regions; a significant increase in IL-1β and IL-6 mRNA started only at 48 hours post-injection, when the induced pain-related behavior started to resolve. Our detailed analysis of CNS glial response clearly revealed that both nerve injury and oro-facial infection/inflammation induced CNS glial activation, but in a completely different pattern, which suggests a remarkable plasticity of glial cells in response to dynamic changes in their microenvironment and different potential involvement of this non-neuronal cell population in pathological pain development.

Gross postmortem and histologic examination findings from abortion losses and calf mortalities in western Canadian beef herds

Production losses from abortions, stillbirths, and early calf mortality were described for the 2002 calf crop in 203 beef herds in western Canada. A total of 1689 calves were examined. A summary diagnosis was reported for 64% of aborted calves, 78% of stillborn calves, 88% of neonatal calves, and 94% of the calves > 3 d of age. Diagnoses for aborted calves included: thyroid gland lesions, pneumonia, developmental anomalies, placentitis, and myocardial necrosis or myopathy. For stillborn calves, diagnostic findings included: dystocia, thyroid gland lesions, myocardial necrosis or myopathy, developmental anomalies, and skeletal myopathy or necrosis. The most common diagnoses for neonatal calves (≤ 3 d) were: pneumonia, skeletal myopathy or necrosis, myocardial necrosis or myopathy, accident or trauma, and septicemia. For older calves (3 d to 3 mo), the most common diagnoses included: starvation, abomasal ulcer or perforation, enteritis or colitis, pneumonia, and intestinal volvulus, obstruction, or perforation.

Clinical cytology and primary health care of children and adults

Clinical cytology is a diagnostic branch of medicine, best known by the Papa test in gynaecology. But, cytology can be applied in almost all fields of clinical medicine. Its advantages--high accuracy, simplicity, with little or no aggressiveness and low cost--are not used as widely as they could be. Medical practice, as well as medical research, and also medical education, are nowadays often directed at profitable use and not at the real benefit of the patient. Primary practitioners do not have enough chance to get acquainted with clinical cytology as a whole although they need true information, based on the cost-effectiveness and patient-benefit. A panel discussion on this subject was organised at the 4th Croatian Congress of Clinical Cytology, in Split, October 11-14, 2009 by the Croatian Society for Clinical Cytology-Croatian Medical Association, to inform primary practitioners about the possibilities of cytodiagnostics in the health care of children and adults. Indications for cytodiagnostics in infectious diseases (T. Jeren and A. Vince), haematology (I. Kardum-Skelin), pulmonology (S. Smojver-Jezek), thyroid diseases (A. Knezević-Obad), breast diseases (I. Kardum-Skelin), gastroenterology and urology (G. Kaić) were discussed, as well as technical procedures and the interpretation of the cytological findings. Moderator (Z. Znidarcić) opened the panel with presentation about the role of clinical cytology, particularly in the primary health care. The discussion finally pointed at the necessity of better communication between primary practitioners and cytologists. This review article presents contents of the panel discussion.

Tractography-based quantitation of corticospinal tract development in premature newborns

OBJECTIVE

To evaluate the impact of early brain injury and neonatal illness on corticospinal tract (CST) development in premature newborns serially studied with diffusion tensor tractography.

STUDY DESIGN

Fifty-five premature newborns (median 27.6 weeks postmenstrual age) were scanned with magnetic resonance imaging (MRI) early in life and at term-equivalent age. Moderate-severe brain abnormalities (abnormal-MRI) were characterized by moderate-severe white matter injury or ventriculomegaly. Diffusion tensor tractography was used to measure CST diffusion parameters which reflect microstructural development: fractional anisotropy (FA) and average diffusivity (D(av)). The effect of abnormal-MRI and neonatal illness on FA and D(av) were assessed with multivariate regression for repeated measures adjusting for age at scan.

RESULTS

Twenty-one newborns (38%) had abnormal-MRI on either scan. FA increased with age significantly slower in newborns with abnormal-MRI (0.008/week) relative to newborns without these MRI abnormalities (0.011/wk) (interaction term P = .05). D(av) was higher in newborns with abnormal-MRI (1.5 x 10(-5) mm(2)/sec; P < .001) for any given age at scan. In the 23 newborns (42%) with postnatal infection, FA increased more slowly (interaction term P = .04), even when adjusting for the presence of abnormal-MRI.

CONCLUSIONS

CST microstructural development is significantly impaired in premature newborns with abnormal-MRI or postnatal infection, with a pattern of diffusion changes suggesting impaired glial cell development.

Control of infection by pyroptosis and autophagy: role of TLR and NLR

Cells can die by distinct mechanisms with particular impacts on the immune response. In addition to apoptosis and necrosis, recent studies lead to characterization of a new pro-inflammatory form of cell death, pyroptosis. TLR and NLR, central innate immune sensors, can control infections by modulating host cell survival. In addition, TLRs can promote the induction of autophagy, thus promoting delivery of infecting pathogens to the lysosomes. On the other hand, activation of some NLR members, especially NLRC4 and NAIP5, leads to the infected cell death by pyroptosis, which is accompanied by secretion of the pro-inflammatory cytokines IL-1beta, IL-18, and IL-33. Data presented here illustrate how the compartmentalization of the innate immune sensors can influence the outcome of infections by controlling the fate of host cells.

B-cell and T-cell phenotypes in CVID patients correlate with the clinical phenotype of the disease

BACKGROUND

Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by recurrent infections and defective immunoglobulin production.

METHODS

The DEFI French national prospective study investigated peripheral T-cell and B-cell compartments in 313 CVID patients grouped according to their clinical phenotype, using flow cytometry.

RESULTS

In patients developing infection only (IO), the main B-cell or T-cell abnormalities were a defect in switched memory B cells and a decrease in naive CD4(+) T cells associated with an increase in CD4(+)CD95(+) cells. These abnormalities were more pronounced in patients developing lymphoproliferation (LP), autoimmune cytopenia (AC), or chronic enteropathy (CE). Moreover, LP and AC patients presented an increase in CD21(low) B cells and CD4(+)HLA-DR(+) T cells and a decrease in regulatory T cells.

CONCLUSION

In these large series of CVID patients, the major abnormalities of the B-cell and T-cell compartments, although a hallmark of CVID, were only observed in half of the IO patients and were more frequent and severe in patients with additional lymphoproliferative, autoimmune, and digestive complications.

Autophagy in infection

Autophagy is a ubiquitous eukaryotic cytoplasmic quality and quantity control pathway. The role of autophagy in cytoplasmic homeostasis seamlessly extends to cell-autonomous defense against intracellular microbes. Recent studies also point to fully integrated, multitiered regulatory and effector connections between autophagy and nearly all facets of innate and adaptive immunity. Autophagy in the immune system as a whole confers measured immune responses; on the flip side, suppression of autophagy can lead to inflammation and tissue damage, as evidenced by Crohn's disease predisposition polymorphisms in autophagy basal apparatus (Atg16L) and regulatory (IRGM) genes. Polymorphisms in the IRGM gene in human populations have also been linked to predisposition to tuberculosis. There are several areas of most recent growth: first, links between autophagy regulators and infectious disease predisposition in human populations; second, demonstration of a role for autophagy in infection control in vivo in animal models; third, the definition of specific antiautophagic defenses in highly evolved pathogens; and fourth, recognition of connections between the ubiquitin system and autophagy of bacteria (and interestingly mitochondria, which are incidentally organelles of bacterial evolutionary origin) via a growing list of modifier and adapter proteins including p62/SQSTM1, NDP52, Atg32, Parkin, and Nix/BNIP3L.

Subungual squamous cell carcinoma masquerading as chronic common infection

Subungual squamous cell carcinoma is a rare disease that has been frequently misdiagnosed as benignity due to lack of awareness among doctors. The author reports a typical case of subungual squamous cell carcinoma in a 49-year-old Thai farmer who presented with a 4-year history of chronic persistent discharging ulcer at the nail bed of the left middle finger after experiencing a minor trauma to the hyponychium. Initially, he was treated as benign infection but the condition did not improve. The nail bed was biopsied and subungual squamous cell carcinoma was finally diagnosed. One small left epitrochlear lymph node and one large left axillary lymph node were palpable. He underwent amputation of the neck of the middle phalanx of the left middle finger and biopsy of ipsilateral epitrochlear lymph node and dissection of the affected axillary tissue. The histological examination confirmed the diagnosis of subungual squamous cell carcinoma with left epitrochlear and axillary lymph node metastasis. Radiotherapy was planned.

Clinical manifestations of Kawasaki disease: what are the significant parameters?

The initial differential diagnosis of Kawasaki disease (KD) from other acute febrile illnesses infants and children is particularly difficult in patients who exhibit incomplete criteria. The objective of this study was to determine the differences in the clinical and laboratory findings between KD patients and those who were initially sus- , pected of having KD but eventually had other diagnoses. One hundred and fourteen pediatric patients who were initially diagnosed with suspected KD were included. Eighteen cases were finally diagnosed with another disease. The only demographic data that were significantly different between the groups were body height and the duration of fever. The KD group exhibited more classical clinical criteria than those who were finally diagnosed with another disease. The erythrocyte sedimentation rate (ESR) and platelet count were significantly higher in the KD group than in the non-KD group. An ESR > or = 40 mm/hour had a diagnostic sensitivity of 90.5%, a specificity of 66.6%, a positive predictive value of 93.4%, and a negative predictive value of 57.1%. The incidence of coronary aneurysm in this study was 6.2%. There was no correlation between ESR and coronary aneurysm. We conclude that the clinical criteria are the basis for the diagnosis of Kawasaki disease but the ESR can be helpful in pediatric patients with acute febrile illness who do not exhibit all clinical criteria.

[Analysis of discrepancies between clinical and autopsy diagnoses in 188 cases]

OBJECTIVE

To analyze the discrepancies between clinical and autopsy diagnoses in hospitals of different grades and with respect to duration of hospitalization.

METHODS

A total of 188 autopsy cases collected from hospitals of different grades were retrospectively reviewed and the discrepancies between clinical and autopsy diagnoses were analyzed.

RESULTS

The overall rate of misdiagnosis was 48.9% (92/188). The misdiagnosis rate in grade I hospitals (75.8%, 25/33) was significantly higher than that in grade III (39.6%, 38/96; chi(2) = 12.861, P = 0.000) and grade II hospitals (49.2%, 29/59; chi(2) = 6.179, P = 0.016 ). The misdiagnosis rate of patients beyond 24 hours of admission was lower than that admitted within 24 hours (chi(2) = 20.991, P = 0.000). The overall rate of missed diagnosis was 34.6% (65/188). The rate of missed diagnosis in grade I hospitals was remarkably higher than that of the grade III hospitals (chi(2) = 8.241, P = 0.006). There was no difference between grades I and III hospitals on the rate of missed diagnosis within 24 hours of admission, however, this rate was lower in grade III hospitals in comparing with that of grade I hospitals in patients admitted beyond 24 hours (chi(2) = 5.181, P = 0.047). The distribution of disease entities commonly encountered in patients of both misdiagnosis and missed diagnosis were heart problems, infections, arterial diseases and pulmonary embolism.

CONCLUSIONS

The rate of discrepancies between clinical and autopsy diagnoses is relatively high. The misdiagnosis and missed diagnosis rate in grade I hospitals was significantly higher than that in grade III hospitals and was closely related with the duration of hospitalization. Autopsy study thus still remains an important measure in clinical audit.

Expression of genes associated with immunity in the endometrium of cattle with disparate postpartum uterine disease and fertility

BACKGROUND

Contamination of the uterine lumen with bacteria is ubiquitous in cattle after parturition. Some animals develop endometritis and have reduced fertility but others have no uterine disease and readily conceive. The present study tested the hypothesis that postpartum cattle that develop persistent endometritis and infertility are unable to limit the inflammatory response to uterine bacterial infection.

METHODS

Endometrial biopsies were collected several times during the postpartum period from animals that were subsequently infertile with persistent endometritis (n = 4) or had no clinical disease and conceived to first insemination (n = 4). Quantitative PCR was used to determine the expression of candidate genes in the endometrial biopsies, including the Toll-like receptor (TLR 1 to 10) family of innate immune receptors, inflammatory mediators and their cognate receptors. Selected proteins were examined by immunohistochemistry.

RESULTS

The expression of genes encoding pro-inflammatory mediators such as interleukins (IL1A, IL1B and IL6), and nitric oxide synthase 2 (NOS2) were higher during the first week post partum than subsequently. During the first week post partum, there was higher gene expression in infertile than fertile animals of TLR4, the receptor for bacterial lipopolysaccharide, and the pro-inflammatory cytokines IL1A and IL1B, and their receptor IL1R2. The expression of genes encoding other Toll-like receptors, transforming growth factor beta receptor 1 (TGFBR1) or prostaglandin E2 receptors (PTGER2 and PTGER4) did not differ significantly between the animal groups. Gene expression did not differ significantly between infertile and fertile animals after the first week postpartum. However, there were higher ratios of IL1A or IL1B mRNA to the anti-inflammatory cytokine IL10, during the first week post partum in the infertile than fertile animals, and the protein products of these genes were mainly localised to the epithelium of the endometrium.

CONCLUSION

Cattle may maintain fertility by limiting the inflammatory response to postpartum bacterial infection in the endometrium during the first week after parturition.

Imaging lesions of the cavernous sinus

Our aim was to review the imaging findings of relatively common lesions involving the cavernous sinus (CS), such as neoplastic, inflammatory, and vascular ones. The most common are neurogenic tumors and cavernoma. Tumors of the nasopharynx, skull base, and sphenoid sinus may extend to the CS as can perineural and hematogenous metastases. Inflammatory, infective, and granulomatous lesions show linear or nodular enhancement of the meninges of the CS but often have nonspecific MR imaging features. In many of these cases, involvement elsewhere suggests the diagnosis. MR imaging is sensitive for detecting vascular lesions such as carotid cavernous fistulas, aneurysms, and thromboses.

A recent perspective on alcohol, immunity, and host defense

BACKGROUND

Multiple line of clinical and experimental evidence demonstrates that both acute, moderate, and chronic, excessive alcohol use result in various abnormalities in the functions of the immune system.

METHODS

Medline and PubMed databases were used to identify published reports with particular interest in the period of 2000-2008 in the subject of alcohol use, infection, inflammation, innate, and adaptive immunity.

RESULTS

This review article summarizes recent findings relevant to acute or chronic alcohol use-induced immunomodulation and its consequences on host defense against microbial pathogens and tissue injury. Studies with in vivo and in vitro alcohol administration are both discussed. The effects of alcohol on lung infections, trauma and burn injury, liver, pancreas, and cardiovascular diseases are evaluated with respect to the role of immune cells. Specific changes in innate immune response and abnormalities in adaptive immunity caused by alcohol intake are detailed.

CONCLUSION

Altered inflammatory cell and adaptive immune responses after alcohol consumption result in increased incidence and poor outcome of infections and other organ-specific immune-mediated effects.

Case report: protothecal tenosynovitis

Protothecosis is a rare infection caused by achlorophyllic algae called Prototheca. Approximately 117 cases have been described in the literature world wide, the majority caused by the species P. wickerhamii. Cutaneous infection is the most common and cases of tenosynovitis are very rare. A local or systemic immunosuppressive factor is seen in half of the cases of protothecosis. We report a case of protothecal tenosynovitis in a middle-aged, immunocompetent woman that developed after she received sclerosing therapy of varicose veins. Administration of itraconazole with surgical débridement produced a good response. We also review the published cases of protothecal tenosynovitis.

Complications in the surgical treatment of craniosynostosis and craniofacial syndromes: apropos of 306 transcranial procedures

OBJECTIVE

To review the complications in the surgical treatment of craniosynostosis in 306 consecutive transcranial procedures between June 1999 and June 2007.

PATIENTS AND METHODS

Surgical series consist of 306 procedures done in 268 patients: 155 scaphocephalies, 50 trigonocephalies, 28 anterior plagiocephalies, one occipital plagiocephaly, 20 non-syndromic multisutural synostosis and 32 craniofacial syndromes (11 Crouzon, 12 Apert, seven Pfeiffer and two Saethre-Chotzen) Complications and time of hospitalisation were reckoned. Surgical procedures were classified in 12 different types according to the technique: Type I: frontal-orbital distraction (26 cases); Type II: endoscopic assisted osteotomies in sagittal synostosis (39 cases); Type III: sagittal suturectomy and expansive osteotomies (44 cases); Type IV: same as type III, but including frontal dismantling or frontal osteotomies in scaphocephalies (59 cases); Type V: complete cranial vault remodelling (holocranial dismantling) in scaphocephalies (13 cases); Type VI: frontal-orbital remodelling without frontal-orbital bandeau in trigonocephaly (50 cases); Type VII: frontal-orbital remodelling without frontal-orbital bandeau in plagiocephaly (14 cases); Type VIII: frontal-orbital remodelling with frontal-orbital bandeau in plagiocephaly (14 cases); Type IX: Occipital advancement in posterior plagiocephaly (one case); Type X: Standard bilateral front-orbital advancement with expansive osteotomies (28 cases); Type XI: holocranial dismantling (complete cranial vault remodelling) in multisutural craniosynostosis (12 cases); Type XII: occipital and suboccipital craniectomies in multiple suture craniosynostosis (six cases).

RESULTS

There was no mortality and all complications resolved without permanent deficit. Mean age at surgery was 6.75 months. Most frequent complication was non-filiated postoperative hyperthermia (13.17% of the cases) followed by infection (8.10%), subcutaneous haematoma (6.08%), dural tears (5.06%) and cerebrospinal fluid (CSF) leakage (2.7%). Number and type of complications was higher among the group of reoperated patients (12.8% of all): 62.5% of all the series infections, 93% of all dural tears and 75% of all CSF leaks. In relation to surgical procedures, endoscopic assisted osteotomies reported the lowest rate of complications, followed by standard frontal-orbital advancement in multiple synostosis, trigonocephalies and plagiocephalies. Highest number of complications was related to complete cranial vault remodelling (holocranial dismantling) in scaphocephalies and multiple synostoses and after the use of internal osteogenic distractors. Special consideration deserves two cases of iatrogenic basal encephaloceles after combined frontal-facial distraction. Finally, we establish considerations based on the complications related to every specific technique.

CONCLUSIONS

Percentage and severity of complications relates to the surgical procedure and is higher among patients going for re-operation. Mean time of hospitalization is also modified by these issues.

Non-ulcerative skin pathologies of the diabetic foot

Many of the complications of the diabetes are well studied but robust research documenting the cutaneous effects of the disease remains sparse. Various studies have suggested that the majority of patients with diabetes will suffer a skin disorder during the course of their disease and for some, the skin changes may even precede the diagnosis of diabetes. Cutaneous pathology of the diabetic foot and lower leg can arise as a result of the direct or indirect effects of diabetic complications. The most common manifestations include fungal and bacterial skin infection, nail disease and diabetic dermopathy. Other less commonly observed conditions include diabetic bullae, necrobiosis lipoidica diabeticorum (NLD), granuloma annulare and reddening of the soles. For many of the less common disorders, there is little in the way of effective treatment. However, much can be done in the clinical setting in the management of the more common manifestations such as bacterial and fungal infection. Fungal infection, in particular, although relatively inconspicuous, is a very common foot problem and if left untreated can threaten tissue viability in the diabetic foot leading to secondary bacterial infection and cellulitis. Management of fungal disease is often considered difficult due to high relapse and re-infection rates, although by introducing a combination of therapies including mechanical and pharmacological the success in treating this stubborn condition can be greatly improved.

[Effects of abdominal infection and intraabdominal hypertension on intestinal interstitial cells of Cajal]

OBJECTIVE

To investigate the influence of abdominal cavity infection and hypertension on the function of intestinal dynamic and interstitial cells of Cajal (ICC).

METHODS

Sprague-Dawley rats were divided into four groups. Group 1 was the sham group. In group 2, infection was induced by cecal puncture and ligation. In group 3, abdominal hypertension was created by placing a catheter into the abdominal cavity, and in group 4, both infection and hypertension were induced simultaneously. Small intestinal transit and in vitro muscle contractions were recorded. Ileum sections stained with hematoxylin and eosin were assessed pathologically. Immunopositivity of c-Kit as markers of ICC and ultrastructures were evaluated by transmission electron microscopy.

RESULTS

Abdominal cavity infection, hypertension and infection plus hypertension decreased the intestinal transit ratios by 14%, 25% and 36% respectively as compared to the sham group. In the bowel segment of the above three groups, muscles showed a significant reduction in frequency and amplitude of contraction. Meanwhile, obvious pathological lesions and smaller positive c-Kit area were found in the above three groups. These changes were associated with the lesions of ICC networks and ultrastructure.

CONCLUSION

Intestinal dysmotility and decrease of c-Kit immunopositivity are induced by abdominal cavity infection and hypertension. ICC plays a central role in maintaining and disrupting the normal intestinal motility in the above conditions.

Chronic inflammation in the cystic fibrosis lung: alterations in inter- and intracellular signaling

A vicious cycle of airway obstruction, infection, and inflammation continues to cause most of the morbidity and mortality in cystic fibrosis (CF). Mutations that result in decreased expression or function of the membrane Cl(-) channel, cystic fibrosis transmembrane regulator (CFTR), result in a decrease in the volume (and hence the depth) of liquid on the airway surface, impaired ciliary function, and dehydrated glandular secretions. In turn, these abnormalities contribute to a milieu, which promotes chronic infection with a limited but unique spectrum of microorganisms. Defects in CFTR also perturb regulation of several intracellular signaling pathways including signal transducers and activator of transcription, I-kappaB and nuclear factor-kappa B, and low molecular weight GTPases. Together, these abnormalities result in excessive production of NF-kappaB dependent cytokines such as interleukin (IL)-1, tumor necrosis factor (TNF), IL-6, and IL-8. There are decreased responses to interferon gamma and transforming growth factor beta leading to decreased production of iNOS and NO. Abnormalities of lipid mediators and decreased secretion of counter/regulatory cytokines have also been reported. Together, these effects combine to create a chronic inflammatory process, which damages and obstructs the airways, and eventually claims the life of the patient.

Infection at the cellular level

Fine structural analysis of the infection process is indispensable for understanding the relation between microorganisms and host cells. This chapter focuses on standard techniques for transmission as well as scanning electron microscopy that will be of benefit even to researchers new to the field.