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Biomedical subjects

G Tritto

Publications and source records attributed to G Tritto.

26 records · Page 2Linked to original sources

[Relationship between taenia coli electric activity and circular fibers. Study of the human transverse colon].

First results of the comparison between the electrical activity of taenia coli and circular muscle are described. Experimental techniques consisted in recording electrical activity for 83 h in 12 patients during the post-operative period after cholecystectomy. Bipolar wire electrodes were surgically inserted in each muscle of the transverse colon's median portion. Statistical treatment leads to the principal conclusion as follows: Whatever type of muscles we have investigated, always could be found slow rhythmic components (called electro-control activity, ECA) in frequency ranges of 1-5 c/min and 9-12 c/min. Major part of taenia coli ECA is in frequency range between 1-5 c/min. ECA in this frequency range can be found in 21% of circular ECA, 23% of taenia coli ECA and 9% of common ECA (% means percents of total recording time). Higher frequencies are found in 7% of circular ECA, 4% of taenia coli ECA and 3% of common ECA. Using long time constant (more than 2 s) the bursts of spikes (10-50 microV) meaning active responses are always accompanied with slower components of important amplitude (greater than or equal to 100 microV): In the discrete mode of activity (DERA) short bursts (during 1-2.5 s) always follow the ECA, whereas in the continuous mode of activity (CERA) mostly longlasting bursts (up to 30 s) could be found. The bursts represent 14% of total time, namely in 8% of longitudinal ECA, 4% of circular ECA and 2% of common ECA. ECA of taenia coli in the case of common ECA is always prolonged. Typical slow waves of greater amplitude (greater than or equal to 500 microV) different from ECA are frequently recorded probably due the intensive contractile process.

Action Potentials↗

[Reorganization of the electrical activity of the transverse colon after cholecystectomy. Study in humans with implanted electrodes].

Electrical activity of the colon was investigated in the postoperative period in 12 patients, 1 to 6 days after cholecystectomy. The polygraphic records are obtained during 2 hours each day late in the morning (10-12 h) in a preprandial situation from serosal implantation of bipolar copper wires inserted into each circular and longitudinal layer in narrow portion of the middle part of the transverse colon. The time presence diagrams was built up after recognition of the basic patterns activity previously definite by Sarna as follows: Electro-Control-Activity, with it slow waves (ECA), Electro-Response-Activity (ERA) with Discrete bursts (DERA) or Continuous ones (CERA). In the former postoperative period 1 to 3 days ECA is present with a low range frequency 1-5 c/min. The higher frequency (10-12 c/min) activity arises sporadically, in this case associated with DERA bursts. From the 4th day all activities ECA and DERA increase significantly. The continuous response activity CERA may be observed in all periods but more frequently from the 3rd day with the same mean duration (12.4 +/- 1.85 s for the circular fibers and 21.6 +/- 2.56 s for the longitudinal ones); the predominance of longitudinal activity duration is significative (p = .001). The complex CEC (26-40 c/min) associated with CERA is observed only in 3% of the time recording. Thus after the onset of colonic motility with DERA and CERA in the 3th day, the normalization is obtain the 6th day with the predominant rythm of 1-2 c/min.

Cholecystectomy↗

[Intraserosal proximal hemideferentectomy versus classical proximal hemivasectomy in the rat. Anatomo-functional aspects and proposal for a new terminology].

According to new trends and terms in microsurgery, the intra-serous proximal hemideferentectomy is compared to the classical vasectomy in rat. The effects of these surgical models are evaluated on morphological and functional bases. The anatomo-pathological parameters considered (stenosis and leakage of the anastomosis of the epididymal tubule conseguent on local ischemia) have been correlated with functional parameters "in vitro" (spontaneous motility and field stimulation) in order to plan the best microsurgical procedure in the experimental tubulo-vasostomy.

Animals↗

[Effects of tubulo-deferens stenosis secondary to intraserosal proximal hemideferentectomy and end-to-end tubulo-vasostomy on the testicle of the rat. Histopathological aspects].

The histopathological aspects of the testis in rat after intra-serous proximal hemideferentectomy and end-to-end tubulo-vasostomy are evaluated. The histomorphometric variations of the convoluted seminiferous tubules and the quantitative modifications of the stages of spermatogenesis are correlated with the obstruction's degree of the tubulo-deferential anastomosis.

Animals↗

Functional evaluation of new experimental model of microsurgical tubulovasostomy in rat.

The function of a new experimental microsurgical model of tubulovasostomy is evaluated. The model is represented by an end-to-end tubulodeferential anastomosis after removal of the proximal (juxtaepididymal) half of the vas deferens and segmental unfolding of the distal part of the epididymal tubule. Both anastomosed segments are evaluated for responsiveness to norepinephrine and field stimulation. The results are discussed in terms of accurate selection of segments to be anastomosed on the basis of their morphofunctional correlates; in fact, it seems worth replacing the segments removed only with others endowed with equivalent properties.

Animals↗

[Effects of radiation emission of the CO2-laser on embryonal ocular bulb tissues (Gallus gallus)].

The wall of the eye bulbs of 15 chick embryos, immediately after their transfer to Hanks fluid, was irradiated with a CO2 laser, focused on the 12th conjunctival papilla or on its prospective area. This 'in vitro' irradiation was performed under the following main parameters: (a) beam power congruent to 4W; (b) exposure time = 1/30 sec; (c) thickness of the fluid (Hanks solution) on the target surfaces = 0, 3 divided by 0, 7 mm. The same area of the eye bulb surface of other 15 chick embryos was irradiated 'in ovo' under the following conditions: (a) congruent to 4W; (b) = 1/10 sec; (c) (amniotic fluid + albumen) = 1 divided by 1, 5 mm. In the L/M analysis so far carried out, the lesions produced 'in vitro' and 'in ovo' showed a number of qualitative resemblances: i.e., disappearance of epithelial cells and numerous pyknoses in the cells left 'in situ'; decrease in thickness of the outer layer of the scleral mesenchyme, whose cells appeared closer to each other-owing to reduction of the intercellular spaces-, and often pyknotic. It is possible that the same mechanisms underlie such morphological aspects, observed in both groups of irradiated eyes. On the other hand, some quantitative differences were observed between the 'in vitro' and 'in ovo' lesions, the extent in surface and depth of the latter being appreciably lesser. Presumably the genesis of such differences could have been influenced by the physico-chemical differences between the fluids covering the target surfaces: Hanks fluid and, respectively, amniotic fluid + albumen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗