Effects of capsaicin,tachykinins, calcitonin gene-related peptide and bradykinin in the pig iris sphincter muscle

Summary Capsaicin-sensitive sensory neurons of the rabbit iris, by releasing tachykinins, exert a major role in the control of pupil motility in response to various noxious stimuli. However, the contribution of sensory innervation to the regulation of iris smooth muscle tone in other mammals species is not known. We have studied the effects produced by electrical field stimulation, capsaicin, substance P, neurokinin A, calcitonin gene-related peptide (CGRP), and bradykinin in the isolated iris sphincter muscle of the pig.Capsaicin (10 M): a) contracted the isolated sphincter muscle and; b) released immunoreactivity for substance P (SP-LI) and CGRP (CGRP-LI) from this preparation. These two effects were no longer observed at the second exposure to the drug. Electrical field stimulation (10 Hz, 60 V, 0.5 ms for 5 s) produced a biphasic contractile response. The rapid component was inhibited by atropine (1 M), while the delayed response was blocked by previous exposure to capsaicin (10 M).Substance P and neurokinin A consistently produced contraction of the pig iris sphincter muscle, substance P being more potent than neurokinin A. CGRP induced a contractile response in more than 50% of the preparations. The tachykinin antagonist [D-Argl, D-Trp^7,9, Leu¹¹-substance P (3 M) blocked: a) the effect of substance P (1 nM); b) the delayed response to electrical field stimulation and; c) reduced by more than 50% response to capsaicin. Bradykinin (10 M) failed to release either SP-LI or CGRP-LI. The contractile response evoked by bradykinin was unaffected by in vitro pretreatment with capsaicin (10 M).The existence in the pig iris of capsaicin-sensitive sensory fibres releasing neuropeptides and thus regulating sphincter muscle tone is proposed. Send offprint requests to Dr. P. Geppetti at the above address     

Capsaicin-like activity of some natural pungent substances on peripheral endings of visceral primary afferents

Summary 1. The effects of some naturally occurring pungent substances, piperine, mustard oil, eugenol and curcumin, were compared to those of capsaicin in the rat isolated urinary bladder. 2. All test compounds dose-dependently contracted the rat bladder and produced desensitization toward capsaicin (1 mol/l). Development of cross-tachyphylaxis among the natural pungent substances on one hand and capsaicin on the other, suggested a common site of action on visceral primary afferents. 3. Contractile responses to piperine, mustard oil and eugenol were partially tetrodotoxin and ruthenium red-sensitive, suggesting that activation of sensory terminals by these agents takes place indirectly, as well as by a direct action on sensory receptors. 4. The presence of the secondary acylamide linkage (present in the backbone of capsaicin, but not in that of test compounds) does not appear to be essential to produce desensitization of sensory nerve terminals. Send offprint requests to R. Patacchini at the above address     

Does the level of stapled ileoanal anastomosis influence physiologic and functional outcome?

PURPOSE: The aim of this investigation was to ascertain how the length of anal canal preserved above the dentate line in stapled end-to-end ileoanal anastomosis influenced late outcome. METHODS: Two groups, high cuff group and low cuff group of nine subjects with stapled anastomosis, matched for sex, age, pouch configuration, and mean follow-up, representing the highest (median, 2.5 cm) and lowest (median, 0.7 cm) anal cuff lengths in our series, were selected. Physiologic and functional parameters were appraised preoperatively, at the time of ileostomy closure, and at 1, 3, 6, and 12 months after reestablishment of intestinal continuity. RESULTS: At one year, the drop in mean anal canal resting pressure was 13 percent in the high cuff group (not signficant) and 31 percent in the low cuff group (P <0.05); mean maximum squeezing pressure did not differ significantly from preoperative values in both groups. The mean volume of the ileal pouch was higher in the low cuff group at all insufflation pressures. The rectoanal inhibition reflex reappeared in four high cuff group patients and in none of the low cuff group patients. Mean distention pressure (cm H ₂ O) and volume (ml) eliciting urge sensation were 80 and 360 in the low cuff group compared with 40 and 240 in the high cuff group (P ?0.05). Daytime bowel movements and night incontinence were significantly better in the low cuff group. No statistical differences were observed for night stool frequency, daytime incontinence, pad use (day and night), discrimination between gas and feces, ability to defer evacuation, and difficulty in emptying the pouch. CONCLUSION: Patients with stapled anastomoses and a low rectal cuff length, despite presenting lower anal resting pressure and absence of rectoanal inhibition reflex, had a better functional outcome in terms of continence than those with a high cuff length.     

Functional analysis of T lymphocytes infiltrating the dermis and epidermis of post-burn hypertrophic scar tissues

The cytokine profile of T cell clones (TCC) from the dermis and epidermis of burn patients with hypertrophic scars (HS) in active (AHS) and remission phases (RHS) was determined in this study. We found that AHS tissues are heavily infiltrated by Type 0-Type 1 polarized CD3+ lymphocytes producing high IFN-gamma and low IL-4 levels. Analysis of their surface marker phenotype showed that the high IFN-gamma production was shared equally between the CD4+ TCRalpha/beta and CD8+ TCRalpha/beta clones. The profile of TCC from RHS tissues revealed pronounced infiltration of Type 0-Type 1 polarized lymphocytes with an even more evident Type 1 profile. However, the levels of IFN-gamma produced by RHS-derived TCC were 4-6 times lower than those produced by AHS-derived TCC. These data show that high levels of IFN-gamma produced by Type 0-Type 1 lymphocytes infiltrating HS are a feature of AHS, whereas reduction of this ability to produce high levels of IFN-gamma, though without a shift towards a Type 0-Type 2 phenotype through an increase in IL-4, is characteristic of RHS.     

Meckel's diverticulum: ten years experience

Meckel's diverticulum (MD) is the most common congenital anomaly of the gastrointestinal tract. The majority of MD cases are asymptomatic although they can, occasionally, cause complications such as bleeding, intestinal obstruction and/or inflammatory process. The diagnosis is difficult and it is usually made at surgery. The treatment of choice in the patients with symptomatic MD is surgical resection while difference of opinion there are about the treatment of asymptomatic MD. The present study concerns 9 cases of MD, 7 symptomatic and 2 incidentally found during surgical abdominal operations. Six patients was males and 3 females with 2:1 male: female ratio. The mean age was 14.7 years. The most common complication was the diverticulitis with the perforation of MD in 1 patient. All patients, symptomatic and asymptomatic, was operated. The diverticulectomy was made in 7 patients while in 2 cases we had to perform an intestinal resection. There was not operative mortality, while there were 2 cases of postoperative complications which occurred only in the patients with symptomatic MD. The Authors believe that there is no factor predictive of the development of diverticular complications. They recommend, in light of the low postoperative mortality and morbidity, the surgical treatment also in the cases of asymptomatic MD, in the absence of absolute contraindications.     

Suppression of tumorigenicity and anchorage-independent growth of BK virus-transformed mouse cells by human chromosome 11.

Viral transformation models may be useful for detecting and mapping human tumor suppressor genes. BK virus (BKV), a human papovavirus, readily transforms rodent cells but is unable to transform human cells, suggesting that oncosuppressive functions expressed in human cells control BKV oncogenic activity. We have transferred human chromosome 11 to BKV-transformed mouse cells. All of the cell clones were suppressed in the tumorigenic phenotype and anchorage-independent growth, except one clone which was nontumorigenic but maintained the ability to grow in soft agar. Cytogenetic analysis and DNA hybridization with chromosome 11-specific probes showed that all the reverted hybrids had an intact human chromosome 11, except the clone growing in semisolid medium which had lost the short arm. The results suggest that a gene located on 11p controls anchorage independence, whereas a gene on 11q controls the tumorigenicity of BKV-transformed cells. BKV T-antigen was expressed in all the hybrid clones at the same level as in the parental cell line, indicating that the putative human tumor suppressor gene(s) do not inhibit expression of the viral oncogene and must operate by another mechanism in inducing reversion of the oncogenic phenotype. Since BKV-transformed mouse cells are highly susceptible to retrovirus infection, this model can be used for searching and cloning tumor suppressor gene(s) by retrovirus-mediated "insertional mutagenesis".     

Radiosurgery in the treatment of the glottic plane carcinoma

During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.