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M Sakka

Publications and source records attributed to M Sakka.

At least 19 recordsLinked to original sources
PubMed2001

Incisive suture (fissure) in the human fetus: radiographic and histologic study.

OBJECTIVE: An anatomic study, in man, of the structure commonly known as the incisive suture (sutura incisiva) or incisive fissure has been performed to determine whether this structure belongs to the morphofunctional concept of a facial suture. MATERIAL: Eighteen palates of human fetuses of 9 weeks to 29 weeks after conception. METHOD: Anatomic, radiographic examination of the palate. Histologic study of sagittal and parasagittal sections of the palates (3 mm each). RESULTS: The histologic aspect is that of a facial suture, with very poor vascularization. This suture is partial, limited laterally by osseous trabeculae. CONCLUSIONS: This particular suture, whose function in growth of the palatal process of the maxilla is discussed, could represent the phylogenetic vestige of the incisive-maxillary suture present in all nonhuman mammals.

Cranial Sutures↗
PubMed2000

Contrasted frequencies of p53 accumulation in the two age groups of North African nasopharyngeal carcinomas.

EBV-associated nasopharyngeal carcinomas (NPCs) from Southeast Asia and North Africa have many common clinical and biological characteristics. However, they differ with regard to their age distribution. In Asia, NPC mainly affects patients in the 4th or 5th decade of their life, whereas in North Africa an additional peak of incidence is found between the ages of 10 and 20. The p53 gene is rarely mutated in NPC. However, several groups have reported a consistent accumulation of p53 in Asian NPCs. To determine whether p53 was also accumulated in North African NPCs, we investigated its expression, by immunohistochemistry, in a series of 90 Tunisian biopsies. Bc12 and CD95, two proteins involved in the regulation of cell survival and apoptosis, were investigated in the same study. We found accumulation of p53 in 81% of the cases for patients over 30 years of age, but in only 38% of specimens for younger patients (P = 0.00013). There was a trend toward a higher frequency of Bc12 detection in patients over 30, but it was not statistically significant. CD95 expression was detected in all biopsies, generally at a high level, even at advanced stages of the disease. The changing frequency of p53 accumulation, below and over 30, suggests that NPC cells often achieve malignant transformation through different pathways in both age groups.

Adolescent↗
PubMed1999

Maxillary ossification in a series of six human embryos and fetuses aged from 9 to 12 weeks of amenorrhea: clinical implications.

An anatomic controversy exists concerning the number of nuclei of ossification of the maxilla in human embryos and fetuses. Many authors have described two maxillary ossification nuclei, an incisor nucleus and a maxillary nucleus properly so-called. Some of these have explained congenital labiomaxillary clefts by a defect of bony fusion between these two ossification nuclei. Others consider that there is only a single nucleus for maxillary ossification. In order to settle this question we performed a histologic study in six heads of embryos and fetuses aged from 9 to 12 weeks of amenorrhea (WA) to demonstrate the presence of one or more sites of maxillary ossification at the earliest stages. Our study revealed, on each side, a single zone of maxillary ossification, present from 9 WA, in the form of a sheet of osteoid tissue situated in close contact with the dental lamina. Maxillary ossification then progressed in the lateromedial direction, preserving a median transverse and ventral mesenchymal septum. This septum may constitute the phylogenetic remnant of an ancestral premaxilla.

Amenorrhea↗
PubMed1996

[Evolutive morphology of the olfactory bulb in man and certain non-human mammals].

Human and comparative anatomy of the olfactory lobe and the anterior floor was studied in 241 patients and 27 specimens (2 human fetuses, 4 specimens from adult humans, 11 non human primates and 10 carnivorous mammals). Macroscopic morphology and imaging data (CT-scan, 3D) reconstruction and magnetic resonance imaging) were obtained at the same time. The results obtained provide radiographic knowledge of the olfactory bulb ontogenesis and a basis for recognizing inborn or acquired pathology of the olfactory bulb. Evidence was also obtained for distinguishing between macrosmatic and microsmatic criteria in mammals.

Adolescent↗
PubMed1995

Reconstruction of the aortic arches of a 28-day human embryo (stage 13) using the Born technique.

We present a reconstruction of the aortic arches of a human embryo at stage 13. Only a few original observations have been reported during the last 110 years and only two with three-dimensional reconstructions. The reconstruction technique originated in 1885. Modern computerized reconstruction techniques have no evident advantages and are more expensive. Aortic arch malformations are responsible for disorders which cannot be understood without a knowledge of their embryology. The embryonic aortic system is a typical example of Haeckel's law of recapitulation. A human embryo at stage 13 was prepared in 5 mm sagittal sections so as to reconstruct the entire dorsal aorta, the second (transient) arch, the third and fourth arches, and the sixth arches responsible for the pulmonary artery, pharynx, larynx and tracheoesophageal axis. They are only 5 pairs of arches in man. At this stage, the most important vessel is represented by the dorsal aorta with a cerebral route, due to predominance of the development of the central nervous system and its vascularisation over other organs. Vascularisation of the lower limbs appears before their macroscopic development and is probably one of the factors responsible for their growth. Many such reconstructions are necessary if conclusions are not to be based on too few specimens to be sound. A better knowledge of embryology lead to a new understanding of aortic arch malformations.

Aorta, Thoracic↗
PubMed1994

Antenatal differentiation of the human intervertebral disc.

To study the antenatal differentiation of the human intervertebral disc, the columns of forty eight embryos and fetuses were examined histologically. The primitive disc is composed of two structures: the notochord which shows a progressive expansion into the disc, and the fibro-cartilaginous perinotochordal disc. No histological sign of interaction between notochordal and perinotochordal cells, which may explain the notochordal expansion into the discs, was seen. On the other hand, the notochordal intervention in the cartilaginous differentiation of the inner zone is probable.

Gestational Age↗
PubMed1994

[Human ontogeny of the left colon. Fetal stage].

Foetal evolution of bowel is the result of unequal growth of its segments and abdominal constraint of pressure. Caecum and appendix on the cranial and right side of intestine torsion differentiate colic anlage. Left colon observations in 20 foetus reveal a dorsal peritoneal fusion between 12 and 17 weeks: Progressive growth of left colon and meso, without dorsal fixation, beyond left kidney and subrenal gland. First mesocolon fixation at the left kidney. A tunnel persist between this fusion and the primitive mesocolon root. Radial advance of peritoneal fusion up to sigmoid mesocolon, with disappearance of the tunnel. Peritoneal fusion confirmed by histology.

Colon↗
PubMed1994

[Volvulus of the superior mesenteric area and congenital variation of the colonic fixation. Human Ontogenesis and Physiopathology. Apropos of a case in an adolescent].

Volvulus of the superior mesenteric territory involving the left and transverse colon is rare. Congenital variations of intestinal fixation have been implicated. We report a case observed in an adolescent which illustrates this hypothesis. There was a fixation of pancreatosplenic region and the left colic angle. The duodenopancreas and the right, transverse and left colon were mobile. Human ontogenesis of the colon could provide a pathophysiologic explanation. During foetal development, the intestine results from unequal growth of the different segments which undergo pressure from the different intra-abdominal contents. The fixation of the different parts of the intestine are independent from each other. Specific circumstances are required for variations in congenital fixation of the colon to led to late events responsible for mechanical volvulus.

Adolescent↗
PubMed1993

[Ontogenic basis of human predisposition to thoracic outlet syndrome. Cervicothoracic reconstruction of a 2.5 cm embryo].

The cervico-thoracic region of a 2.5 cm embryo, that means approximately 7 weeks old or Streeter stage 20, has been reconstructed in 3 dimensions, with the Born procedure. Scaleni muscles are separated in 2 groups by the brachial plexus, which emerges directly with an antero-external course to the pectoral limb. The loco-regional anatomical arrangement, particular of that age, combining: a scapulum situated in a para-sagittal plane, a clavicle situated in a high transverse plane, a cervical kyphotic curve, and a keeled chest aspect, remind the quadriped morphology, and point out the real metamorphosis later sustained by the foetus. The Cervico-Cephalic Emergence defined in human by Sakka (1973), will later overturn the regional architecture, modifying directions and forms of skeletal structures, on which scalene muscles insert. The initially direct brachial plexus course will secondary turn to an angle, to fit on morphological changes of the surrounding preestablished elements; a certain ontogenic foundation for the anatomical propensity to thoracic outlet syndrome could then be explained.

Embryo, Mammalian↗
PubMed1991

[Parameters of the facial bones in the fetus. Anthropology and medico-legal application for the determination of the fetal age].

From 93 skulls and 23 foeto-skeletals we give a glimpse of the rhythme of the human foetuse's facial bones growth and the main variations for facial measurements rating during foetal period. The best correlation between foetal age and facial measurements was obtained with facial height (correlation coefficient: 0.96). Evolution of cranio-facial rating, during foetal stages shows essentially: the increase of the height/width facial rating, the same rhythme of growth for frontal and facial width, the rapidly growth of biparietal diameter up to 30 amenorrhea weeks comparatively to the facial and frontal growth in width.

Age Determination by Skeleton↗
PubMed1991

[One liver for 2 transplantation recipients. How to divide the portal pedicle?].

It is possible to obtain two hepatic transplants from a single cadaveric liver by separation or right and left livers or by separation of the right lobe from the left lobe medial to the umbilical cleft. We attempt to define the ideal basis of separation of the structures of the portal pedicle, based on anatomical study of 25 livers. One should ideally section the left portal vein, the right branch of the hepatic artery, the left hepatic duct. The segment I must be systematically resected, the segment IV must be resected after a separation of the right lobe from the left lobe. A cholangiogram and an arteriogram are indispensable prior to hepatic division.

Dissection↗
PubMed1990

[Amplification of mitochondrial DNA fragments from ancient human teeth and bones].

We extracted and visualized DNA from ancient human teeth and bones of 150 to 5,500 years B.P. from three deposits from the south of France. The DNA extracted was used as template for PCR with specific primers corresponding to a portion of the human mitochondrial genome. In our samples, we have amplified a specific DNA fragment of 121 bp which, in the case of one bone of 150 years B.P. has been cloned and sequenced. We show that this sequence is identical to the homologous region of human mitochondrial DNA. The striking implications of this new method for archaeological and paleontological studies are exposed.

Base Sequence↗
PubMed1987

An epidemic of hepatitis A in an institution for young children.

A common-source epidemic of hepatitis A occurred in an Athenian institution boarding 38 children (mean age 4.8 years). All children were examined, and blood was drawn from each at the onset of the study and repeatedly during the next three months. Only one child (2.6%) was initially immune to hepatitis A virus as a result of prior infection. The attack rate (62.2%) and the ratio of icteric to anicteric cases (1:1.3) were high despite the administration of immunoglobulin (IG). Assays for anti-HAV IgM and a rising titer of anti-HAV IgG identified 19 (82.6%) and 22 (95.7%) of the 23 hepatitis A infections, respectively. One case (4.3%) was detected only by the presence of hepatitis A virus antigen and hepatitis A virus RNA in a fecal specimen, but these assays were otherwise marginally useful in this study. Nevertheless, the use of all available tests for the detection of hepatitis A virus is mandatory for the most accurate estimation of an epidemic of hepatitis A. Prompt administration of immunoglobulin had no effect on the number of clinical cases that were in the late incubation period, but it may have diminished the clinical expression of the infection and thus made diagnosis of infection more difficult.

Child↗
PubMed1987

[Comparative anatomy of the velopharyngeal complex in mammals--excluding primates (1)].

From the anatomic element known with the man by the name of soft palatal-pharyngeal sphincter and which takes a major part in the phonation, the swallowing, the breathing, we have studied the evolutive morphology of the soft palatal-pharyngeal unity in several mammals. This unity which includes the levator palati and palatopharyngeus muscles is confirmed by the phylogenic and embryologic investigations. The comparative anatomy of the rat, rabbit, sheep and lion, allows to make obvious a evolutive line characterized by the gradual divergence of the axis of the two muscles common to the soft palatal and pharyngeal musculature, which could correspond with a phylogenic evolution.

Anatomy, Comparative↗