Visceral hypersensitive rats share common dysbiosis features with irritable bowel syndrome patients

AIM: To evaluate gut microbial dysbiosis in two visceral hypersensitive models in comparison with irritable bowel syndrome (IBS) patients and to explore the extent to which these models capture the dysbiosis of IBS patients.

METHODS: Visceral hypersensitivity was developed using the maternal separation (MS) rat model and post-inflammatory rat model. The visceral sensitivity of the model groups and control group was evaluated using the abdominal withdraw reflex score and electromyography in response to graded colorectal distention. The 16S ribosomal RNA gene from fecal samples was pyrosequenced and analyzed. The correlation between dysbiosis in the microbiota and visceral hypersensitivity was calculated. Positive findings were compared to sequencing data from a published human IBS cohort.

RESULTS: Dysbiosis triggered by neonatal maternal separation was lasting but not static. Both MS and post-inflammatory rat fecal microbiota deviated from that of the control rats to an extent that was larger than the co-housing effect. Two short chain fatty acid producing genera, Fusobacterium and Clostridium XI, were shared by the human IBS cohort and by the maternal separation rats and post-inflammatory rats, respectively, to different extents. Fusobacterium was significantly increased in the MS group, and its abundance positively correlated with the degree of visceral hypersensitivity. Porphyromonadaceae was a protective biomarker for both the rat control group and healthy human controls.

CONCLUSION: The dysbiosis MS rat model and the post-inflammatory rat model captured some of the dysbiosis features of IBS patients. Fusobacterium, Clostridium XI and Porphyromonadaceae were identified as targets for future mechanistic research.

Clinical profile of Guillain Barre syndrome

OBJECTIVES

To study clinical presentation, hospital care and outcome of patients of Guillain Barre Syndrome (GBS) and number of patients of respiratory failure and need for ventilators. To study efficacy of IVIg in patients of GBS.

MATERIAL AND METHODS

40 patients of GBS studied in detail including history, clinical examination and investigations (Nerve conduction velocity and C.S.F. examination). All patients were watched for respiratory insufficiency and those who developed respiratory paralysis were given assisted mechanical ventilation. Patients were treated with IVIG and outcome was observed. Outcome of 2 groups of patients one treated with IVIg and other not treated with IVIg (supportive line of treatment) were compared.

RESULTS

Commonest age group affected was 13-40 yrs. The male:female ratio was 1.5:1. Antecedent infection in form of fever, cough [11 patients], loose motions [10 patients] were present in 21 out of 40 patients. Quadriparesis was present in 39 patients and paraparesis in 1 patient. Cranial nerve involvement was seen in 25 out of 40 patients. Facial nerve was involved in 12 [30%] patients and Glossopharyengeal, vagus nerves were involved in 12 [30%] patients. Areflexia was found in all 40 patients. In CSF examination, albuminocytologic dissociation was present in 17 out of 26 patients. NCV findings show conduction velocity slowing, delayed f latencies in 90% patients. Out of 40 patients, 13 [30%] required mechanical ventilation. Out of 40 patients, 14 were treated with IVIg, 4 patients treated with plasmapheresis and 22 patients received only supportive treatment. Out of 40 patients 30 [75%] patients recovered completely, 8 [20%] patients died and 2 [5%] patients developed severe neurologic deficit.

CONCLUSION

GBS is more common in 13-40 yrs age group with male:female ratio of 1.5:1. Antecedent infection is seen in 55% patients. Commonest presentation was paresthesia in legs and ascending paralysis. One third [32.5%] patients developed respiratory paralysis and needed ventilatory support. Patients who received IVIg early in the course of disease had faster recovery as compared to patients who received only supportive line of treatment.

Characteristics of intestinal lamina propria dendritic cells in a mouse model of postinfectious irritable bowel syndrome

BACKGROUND AND AIM

Postinfectious irritable bowel syndrome (PI-IBS), which results from inflammation has been emphasized a lot recently. Dendritic cells (DCs) may contribute to intestinal mucosal immune activation in the pathogenesis of PI-IBS. This study tested the hypothesis that phenotype and function of intestinal lamina propria DCs (LPDCs) changed in the development of a PI-IBS mouse model.

METHODS

Mice infected with Trichinella spiralis underwent abdominal withdrawal reflex (AWR) to evaluate visceral sensitivity. LPDCs were isolated and purified by intestine digestion and magnetic label-based technique. Surface markers were analyzed by flow cytometry. Endocytic activity, mixed lymphocyte reaction (MLR) and chemotaxis were studied. Cytokine production of the LPDCs cocultured with CD4(+) T cells was determined.

RESULTS

Intestinal inflammation resolved after 8 weeks infection with sustained visceral hyperalgesia. Surface markers CD86 and MHCII were lower in the acute infection group, but increased in the PI-IBS stage. Enhanced ability of endocytic activity and decreased abilities to attract and stimulate CD4(+) T cell proliferation were in the acute infection group. However, LPDCs in the PI-IBS stage showed weakened endocytic ability with enhanced abilities to attract and stimulate CD4(+) T cell proliferation. Cocultured LPDCs with CD4(+) T cells showed a predominant Th2 response in the acute infection stage, and more important roles of Th1, Th17 responses in the PI-IBS stage.

CONCLUSIONS

The hypothesis was supported that the phenotype and function of LPDCs changed in the development of PI-IBS, which induced the maintenance of intestinal mucosal immune activation and might provide a clue for the treatment of the disease.

Increased startle responses in interstitial cystitis: evidence for central hyperresponsiveness to visceral related threat

PURPOSE

Hypersensitivity to visceral stimuli in interstitial cystitis/painful bladder syndrome may result from enhanced responsiveness of affective circuits (including the amygdala complex) and associated central pain amplification. Potentiation of the eyeblink startle reflex under threat is mediated by output from the amygdala complex and, therefore, represents a noninvasive marker to study group differences in responsiveness in this brain circuit.

MATERIALS AND METHODS

Acoustic startle responses were examined in female patients with interstitial cystitis/painful bladder syndrome (13) and healthy controls (16) during context threat (application of muscle stimulation electrodes to the lower abdomen overlying the bladder), and cued conditions for safety (no stimulation possible), anticipation and imminent threat of aversive abdominal stimulation over the bladder.

RESULTS

Patients showed significantly greater startle responses during nonimminent threat conditions (baseline, safe and anticipation periods) while both groups showed similar robust startle potentiation during the imminent threat condition. Higher rates of anxiety and depression symptoms in the patient group did not account for the group differences in startle reflex magnitude.

CONCLUSIONS

Compared to controls, female patients with interstitial cystitis/painful bladder syndrome showed increased activation of a defensive emotional circuit in the context of a threat of abdominal pain. This pattern is similar to that previously reported in patients with anxiety disorders as well as those with irritable bowel syndrome. Since these circuits have an important role in central pain amplification related to affective and cognitive processes, these results support the hypothesis that the observed abnormality may be involved in the enhanced perception of bladder signals associated with interstitial cystitis/painful bladder syndrome.

[Lhermitte's sign]

Besides Babinski's, Lhermitte's sign is likely the eponym mostly used in the neurological literature. We review here the history of this eponym as well as recent advances on its pathophysiology and treatment. Lhermitte's phenomenon is, on one hand, a symptom as it is spontaneously explained by patients, and, on the other hand, a sign as it may be triggered by flexion of the nape. Initially described after head and cervical spine trauma, firstly by Marie and then by Babinski, it was Jean Lhermitte who recognized on it an etiological specificity, namely, a demyelinating sign of cervical spinal posterior cords. He also made a pathophysiological interpretation of the phenomenon, namely, a stretching of posterior cords during flexion of the neck. All authors agree that this phenomenon is more common in multiple sclerosis, although it has been descibed in many other conditions. The history of how this sign was hatched, whose pathophysiology remains a mystery, is fascinating. And it is fascinating the fact that patients compare the phenomenon with a current, especially if we bear in mind that few people may have suffered an electrocution, mainly in that time when just a few ones could actually enjoy domestic electricity.

The gastrorectal reflex in women with obstructed defecation

This study evaluated the tonic response of the rectum to a meal in women with obstructed defecation. Fifteen control subjects and 60 women with obstructed defecation were studied. Total colonic transit time was normal in 30 patients (group I) and prolonged in the other 30 (group II). After over-night fasting an "infinitely compliant" polyethylene bag was inserted into the rectum. Rectal tone was assessed by measuring variations in bag volume with a computerized electromechanical air injection system. After an adaptation period of 30 min all subjects consumed a 450-kcal liquid meal. Postprandial recordings were continued for 3 h. In a second recording session we investigated the tonic response of the rectum to an evoked urge to defecate. In a third session rectal sensory perception was assessed. Following the meal all controls showed an increase in rectal tone (mean 74.8 +/- 17%). Patients in whom colonic transit time was normal showed a similar tonic response. In group II the increase in rectal tone was significantly lower (mean 27.8 +/- 10%; P < 0.001). Three patients of this group showed no response to a meal at all. All controls showed an increase in rectal tone during an evoked urge to defecate (mean 39.2 +/- 9%). In both groups this tonic response was absent or significantly blunted (mean 15.3 +/- 6% and 16.4 +/- 5%, respectively; P < 0.001). In both groups rectal sensory perception was significantly impaired. In conclusion, patients with obstructed defecation in whom colonic transit time is normal have an intact gastrorectal reflex. The increase in rectal tone after a meal is absent or blunted in patients with obstructed defecation in whom transit time is prolonged. The tonic response of the rectum to an evoked urge to defecate as well as rectal sensory perception are significantly impaired both in patients with a normal and in those with a prolonged transit time.

Induction and organization of Ca2+ waves by enteric neural reflexes

The motility of the gastrointestinal tract consists of local, non-propulsive mixing (pendular or segmental) and propulsive (peristaltic) movements. It is generally considered that mixing movements are produced by intrinsic pacemakers which generate rhythmic contractions, and peristalsis by intrinsic excitatory and inhibitory neural reflex pathways, but the relationship between mixing and peristalsis is poorly understood. Peristalsis is compromised in mice lacking interstitial cells of Cajal, suggesting that these pacemaker cells may also be involved in neural reflexes. Here we show that mixing movements within longitudinal muscle result from spontaneously generated waves of elevated internal calcium concentration which originate from discrete locations (pacing sites), spread with anisotropic conduction velocities in al directions, and terminate by colliding with each other or with adjacent neurally suppressed regions. Excitatory neural reflexes control the spread of excitability by inducing new pacing sites and enhancing the overall frequency of pacing, whereas inhibitory reflexes suppress the ability of calcium waves to propagate. We provide evidence that the enteric nervous system organizes mixing movements to generate peristalsis, linking the neural regulation of pacemakers to both types of gut motility.

[Expiration-like movement and spino-bulbo-spinal reflex in a patient with apneic coma caused by anoxic encephalopathy]

A 72-year-old female patient, hospitalized for parkinsonism, suffered cardiopulmonary arrest without any certain causes. The patient was successfully resuscitated and her life was sustained by artificial ventilator for 100 days. All brainstem reflexes were absent, and flat electroencephalogram and no response of brainstem auditory evoked potentials were confirmed twice with an interval of over 6 hours. Flexion of the arm induced reflex rectus abdominis muscle contraction, resembling expiratory movement. Muscle stretch reflexes on rectus abdominis were hyperactive. The expiration-like movement appeared in an apnea test seven minutes after a cessation of artificial ventilation. Electrical stimuli on femoral nerve induced complex action potentials with a 70.2 +/- 6.9 msec latency and 300 msec duration in rectus abdominis muscle, which were similar to the spino-bulbo-spinal reflex. Single photon emission tomography showed only slight cerebral cortical blood flow. The expiration-like movements observed in this case suggest a relationship not only with the spinal cord reflex but also with polysynaptic reflexes to reticular formation in the medulla oblongata.

Postoperative pain and superficial abdominal reflexes after posterolateral thoracotomy

BACKGROUND

Posterolateral thoracotomy can produce stretching of/or damage to the intercostal nerves and their branches. To assess intercostal nerve impairment after operation, we measured the superficial abdominal reflexes, which are mediated, at least in part, by the most inferior intercostal nerves.

METHODS

Using electrophysiologic techniques, we made recordings from the left and right abdominal walls to study the responses evoked by mechanical stimulation of the skin after operation. In addition, we assessed postoperative pain intensity according to a numeric rating scale and recorded postoperative opioid dose.

RESULTS

We found that the patients with complete disappearance of the superficial abdominal reflexes experienced more severe postoperative pain than those in whom the reflexes were maintained. Moreover, opioid treatment was less effective in the patients with no reflexes postoperatively.

CONCLUSIONS

Our findings show a strict correlation between pain intensity after posterolateral thoracotomy and absence of abdominal reflexes. We suggest that the higher pain intensity together with the absence of reflexes may be due to intercostal nerve impairment, be it anatomic or functional, and thus to a larger neuropathic component of postoperative pain. This finding may be used as a predictor of patients with high analgesic requirements.

[A case of the abdominal form of Wilson's disease with atypical clinical symptoms in a 19-year-old man]

A case of the abdominal form of Wilson's disease is described in a male patient aged 19 years. The case progressed rapidly and presented rarely observed signs of central nervous system damage. Morphological examination of the brain demonstrated well developed picture of tissue damage characteristic of this disease entity.

A note on the deep abdominal reflex

Deep abdominal reflexes were recorded electromyographically in six patients with lesions of the upper motor neuron. The responses were bilateral, usually with identical latencies which ranged from 16.5 to 25 ms. Individual variation was never greater than 2 ms. It is postulated that these bilateral responses of abdominal muscles were independent stretch reflexes and were not mediated across the midline through an intraspinal pathway.

[Acute abdomen masking pyelonephritis (author's transl)]

Analysis of 10 case histories shows that the picture of the acute abdomen may predominate in acutely exacerbated pyelonephritis. Viscero-dermal reflexes with hyperalgesia and muscular defense, visero-visceral organ reflexes with shock, vomiting, meteorism and disturbances of intestinal motility and metabolic acidosis are temptations to laparotomy. Fever in particular, pathological urinalysis, renal acidosis and occasionally hyperchloremia suggest the diagnosis of "abdominal type of acutely exacerbated pyelonephritis".

[Pheochromocytoma and Recklinghausen's cutaneous neurofibromatosis. Localizing value of abdominal reflexes in a case]

The authors present a case of pheochromocytoma observed in a 49 year old man suffering from the cutaneous form of von Recklinghausen's disease. In this patient, they noted the constant absence of the inferior abdominal cutaneous reflex on the right side, contrasting with the briskness of the other abdominal cutaneous relexes. From this they concluded that the chromaffin tumor was very probably situated in the right adrenal region. This hypothesis was confirmed by retro-pneumoperitoneum, selective arteriography and finally surgical intervention. After having reviewed the essential medical data from the literature concerning the conditions associated with pheochromocytoma and especially phacomatosis, and having looked at the problem of hypertension related to neurofibromatosis, they make a critical study of the behaviour of the abdominal reflexes in case of pheochromocytoma and emphasize the part that it is possible to draw from this in view of its' topographic diagnosis. The present case is the fourth in which one of the authors has noted the abolition of the inferior abdominal reflex on the side corresponding to the site of the pheochromocytoma.

Diagnosis and prognosis of acute cervical spinal cord injury

The diagnosis of complete or incomplete quadriplegia and designation of functional levels can be accurately determined during the first 24 hours after injury in virtually all cases of severe traumatic quadriplegia. The prognosis for recovery depends upon an understanding of regeneration of nerve roots following injury and the significance of return of involuntary reflex activity. A realistic prognosis and accurate evaluation of various forms of treatment depend upon accurate documentation of the pattern of sensory and motor deficits.

[Chronic bleeding into the syringomyelic cavity (Gower's syringal hemorrhage)]

The authors describe a rare case of chronic bleeding into the syringomyelic cavity treated surgically. Bleeding caused slowly increasing manifestations of disease after 23 years of stationary phase. The cause of such bleedings is unknown.

Lumbar vertebral innervation and intra-abdominal pressure

Images

Familial postero-lateral myelopathy and angiomatosis retinae

Two sisters and a brother suffering from progressive spastic paraparesis and severe deep sensitivity loss were presented. In 2 of them, angiomatosis retinae was demonstrated by ophthalmological examination. The differential diagnosis of this neurological clinical syndrome is discussed.