Search

The apical hook of dark-grown dicotyledonous plants results from asymmetric growth of the inner and outer sides of the upper part of the hypocotyl. This protective structure prevents damage of the shoot apical meristem and the young leaves as the seedling pushes through the soil. HOOKLESS (HLS1) of Arabidopsis was recognised as an ethylene response gene whose product is required for hook formation. We cloned two cDNAs from tomato, Sl-HLS1 and Sl-HLS2, and showed through the complementation of the Arabidopsis hls1 mutant that the encoded proteins are functional orthologs of At-HLS1. The genomic clones of Sl-HLS1 and Sl-HLS2 showed similar structure with two introns and three exons. While the data indicate complete functional redundancy between the two tomato HLS genes, only the expression of Sl-HLS2 is regulated by ethylene and auxin and the ethylene-induced expression of Sl-HLS2 is localised in the outer side of the hook while the auxin-responsive expression is not restricted to a specific side of the hook. 1-MCP, an inhibitor of ethylene signalling, inhibited auxin-enhanced accumulation of Sl-HLS2 mRNA in the apical hook suggesting that regulation of Sl-HLS2 by auxin is ethylene-dependent. The overexpression of tomato Sl-HLS1 and Sl-HLS2 in Arabidopsis confers hypersensitivity to ethylene. The data presented bring further insight into the complex ethylene-auxin interplay in hook formation., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Background: Ascitic decompensation is a common major complication of cirrhosis and is associated with a poor outcome. In 5-10% of patients, ascites become resistant to treatment (either do not respond to a high dose of diuretics or because these drugs induce complications), which is called refractory ascites (RA). RA is associated with poor survival: 20-50% at 1 year. The aim of this study was to investigate the outcome of RA., Methods: Retrospective study including consecutive cirrhotic patients admitted for controlling ascites between January 2010 and April 2013. Patients and cirrhosis characteristics were studied. Development of RA during follow-up was investigated. The impact of RA on the outcome (cirrhosis complications and survival) was evaluated., Results: We included 124 cirrhotic patients: 59 females (47.6%); mean age was 58 years. Ascites was grade 3 in 38.5% and was the first episode in 45.1% of patients. Etiology of cirrhosis was mainly viral (57.3%). Child-Pugh score was B in 39.5% and C in 28.2%. Mean MELD score was 16 [6-40]. During follow-up, 27 patients developed RA, meaning a prevalence of 21.8%. RA type was diuretic intractable in all cases. Survival without complications was significantly reduced in patients with RA (4 vs 17 monthsp<10-3). RA was an independent predictive factor of global complications, spontaneous bacterial peritonitis and hepatic encephalopathy. Global survival was reduced in patients with RA (12 vs 16 months, p=0.069). One year survival was 45% for patients with RA vs 63% for other cirrhotics. In multivariate analysis, only Child-Pugh score, but not RA was an independent prognostic factor., Conclusion: In this Tunisian sample we confirm that RA reduces survival and increases risk of cirrhosis complications, especially hepatic encephalopathy and spontaneous bacterial peritonitis. Therefore, these patients should be promptly listed for liver transplantation, over and above the MELD score.

Purpose: To define epidemiological, clinical, therapeutic and prognostic factors influencing survival of breast cancer in young women younger than 35 in southern Tunisia., Material and Methods: This is a retrospective study of 83 patients younger than 35 years and treated within tumors mammary committee of Sfax., Results: The mean age was 31.7 years. T2 stage, high grade with positive node tumors were frequent. Breast surgery was performed for 73 patients. Chemotherapy was neo-adjuvant, adjuvant and palliative for respectively 10, 62 and 13 patients. Radiotherapy was delivered for 65 patients with curative intent and for 8 metastatic patients. Endocrine therapy was adjuvant in 38 patients and palliative in 6 cases. The overall survival (OS) at 5 years was 66.8%. Pejorative prognostic factors in uni-variate analysis were clinical T stage (T3, T4), and the number of involved lymph nodes., Conclusion: Despite adequate treatment, the prognosis of breast cancer in young women remains worse. Early diagnosis is necessary to promote outcome.

The plant hormone auxin plays a central role in adventitious rooting and is routinely used with many economically important, vegetatively propagated plant species to promote adventitious root initiation and development on cuttings. Nevertheless the molecular mechanisms through which it acts are only starting to emerge. The Arabidopsis superroot2-1 (sur2-1) mutant overproduces auxin and, as a consequence, develops excessive adventitious roots in the hypocotyl. In order to increase the knowledge of adventitious rooting and of auxin signalling pathways and crosstalk, this study performed a screen for suppressors of superroot2-1 phenotype. These suppressors provide a new resource for discovery of genetic players involved in auxin signalling pathways or at the crosstalk of auxin and other hormones or environmental signals. This study reports the identification and characterization of 26 sur2-1 suppressor mutants, several of which were identified as mutations in candidate genes involved in either auxin biosynthesis or signalling. In addition to confirming the role of auxin as a central regulator of adventitious rooting, superroot2 suppressors indicated possible crosstalk with ethylene signalling in this process.

The extranodal non-Hodgkin lymphomas of maxillofacial soft tissues are rare. We report two cases of maxillofacial soft tissue non-Hodgkin lymphoma treated with chemotherapy followed by localized radiotherapy with complete remission after 3 and 6 months. We study the clinical, radiological and histopathological features as well as the treatment and the prognosis of extranodal non-Hodgkin lymphomas maxillofacial muscles., (Copyright © 2013 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.)

In this study xylanase from Penicillium occitanis Pol6, as a bread improver, was tested in whole-wheat bread. The purified xylanase termed PoXyn2 was used as an additive at a very small quantity (0.12 U/g flour basis) during mixing of wheat flour. The effects of xylanase addition on the fermentation stage and the final bread quality were analyzed. Remarkable decrease (8%) in water absorption and increase in dough rising (36.8%) were noticed. Final moisture content of the bread was higher (37.50%) than control (23.56%). Improvements in volume (17.8%) and specific volume (34.9%) were also significant. Sensory evaluation indicated better flavor, taste, softness and overall acceptability. Texture profile analysis confirmed the rheological changes. Firmness was decreased by more than twofolds. Improvements in cohesiveness and decline in springiness and gumminess were observed. PRACTICAL APPLICATIONS: The baking industry is shifting toward producing whole-wheat fiber-rich bread using enzymes such as xylanase, which can improve dough machinability and stability, oven spring, loaf volume, crumb structure and shelf life. This hypothesis is supported by determining the functional and rheological properties of supplemented dough with purified Penicillium occitanis xylanase. The improved bread was assessed by a panel of five judges for sensory evaluation. Furthermore, significant improvement in textural properties was noticed., (© 2012 Wiley Periodicals, Inc.)

Intracellular thermostable esterase produced by the extremophilic Geodermatophilus obscurus G20 was purified to homogeneity by a heat treatment, followed by an anion-exchange chromatography, and then characterized. The molecular weight of the purified enzyme determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was shown to be approximatively 55 kDa. The enzyme showed an optimal activity between pH 8.0 and 9.0 and was stable in the pH range 7.0-10.0. Moreover, it is highly thermostable, with a residual activity greater than 90% after incubation at 80 °C for more than 10 h. The enzyme showed preference for esters of p -nitrophenol with short chain fatty acid. When the p -nitrophenyl acetate (C2) was used as substrate, the Michaelis-Menten constant (K(m) ) and maximum velocity for the reaction (V(max) ) of esterase were 400 μM and 2500 U/mg protein, respectively. The effect of phenylmethanesulphonyl fluoride (PMSF), a serine-specific inhibitor, on the enzyme activity suggested that the thermostable esterase belong to the serine hydrolase group. Because of its high thermostability, activity at alkaline pH, tolerance to methanol and various metal ions and specificity for short chain fatty acids, this enzyme showed high potential for use in biocatalysis. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nutritional requirements can contribute considerably to the production cost and the bioprocess economics. Media optimisation using response surface methodology is one of the used methods to ameliorate the bioprocess economics. In the present study, biosurfactant production by Bacillus subtilis SPB1 was effectively enhanced by response surface methodology. A Plackett-Burman-based statistical screening procedure was adopted to determine the most important factor affecting lipopeptide production. Eleven variables are screened and results show that glucose, K(2)HPO(4), and urea concentrations influence the most biosurfactant production. A Central Composite Design was conducted to optimize the three selected factors. Statistical analyses of the data of model fitting were done by using NemrodW. Results show a maximum predicted biosurfactant concentration of 2.93 (±0.32) g/L when using 15 g/L glucose, 6 g/L urea, and 1 g/L K(2)HPO(4). The predicted value is approximately 1.65 much higher than the original production determined by the conventional one-factor-at-a-time optimization method.

During the last years, several applications of biosurfactants with medical purposes have been reported. Biosurfactants are considered relevant molecules for applications in combating many diseases. However, their use is currently extremely limited due to their high cost in relation to that of chemical surfactants. Use of inexpensive substrates can drastically decrease its production cost. Here, twelve solid substrates were screened for the production of Bacillus subtilis SPB1 biosurfactant and the maximum yield was found with millet. A Plackett-Burman design was then used to evaluate the effects of five variables (temperature, moisture, initial pH, inoculum age, and inoculum size). Statistical analyses showed that temperature, inoculum age, and moisture content had significantly positive effect on SPB1 biosurfactant production. Their values were further optimized using a central composite design and a response surface methodology. The optimal conditions of temperature, inoculum age, and moisture content obtained under the conditions of study were 37°C, 14 h, and 88%, respectively. The evaluation of the antimicrobial activity of this compound was carried out against 11 bacteria and 8 fungi. The results demonstrated that this biosurfactant exhibited an important antimicrobial activity against microorganisms with multidrug-resistant profiles. Its activity was very effective against Staphylococcus aureus, Staphylococcus xylosus, Enterococcus faecalis, Klebsiella pneumonia, and so forth.

Cardiac hydaticyst is a rare condition and accounts for only 0.5 to 2% of all visceral locations of hydatid disease. The objective of this study was to point out the main clinical, radiological, and disease-course characteristics of this rare and serious pathology. We report a 13-year-old patient with a hydatid pulmonary embolism caused by a hydatid cyst of the interauricular septum. The diagnosis was established by transthoracic echocardiography, thoracic CT scan, and hydatid serology. Surgery was performed without delay and the outcome was good after 15 months of follow-up. This case underlines the need for rapid diagnosis and surgery before complications of cardiac hydatid cyst., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Background: Ovarian cancer is the leading cause of death from gynaecological malignancies. Newer biological prognostic factors and predictors of response to therapy are needed. Our study was designed to evaluate the expression of p53, Bcl-2, Estrogen receptor (ER) and Progesterone receptor (PR) in ovarian carcinoma and to compare it with other prognostic parameters such as age, FIGO stage, size of residual tumor, histological type and grade., Methods: This is a retrospective study conducted in the department of pathology at Sfax University Hospital. Confirmed 57 cases of ovarian carcinoma were reviewed in the period between January 1995 and December 2006. We used immunohistochemistry to evaluate the expression of p53, Bcl-2, ER and PR receptors and Chi-Square and Student test to correlate immunohistochemical findings with some prognostic parameters of ovarian carcinoma., Results: The percentage of expression of p53, Bcl-2, ER and PR was 73,7; 47,4; 35,1 and 33,3 % respectively. p53 overexpression correlated with an advanced FIGO stage (p = 0,026) and presence of ascitis (p < 10 -4 ). The expression of PR was associated with an early stage (FIGO I and II), a non serous histologic type and a low tumour grade (p = 0,045; 0,010 and 0,036 respectively). No correlation was found between Bcl-2 and ER and prognostic parameters. Survival analysis revealed that Bcl-2 status, FIGO stage, presence of ascites, peritoneal cytology, and residual disease were significant predictive factors of survival., Conclusion: p53 expression correlates with a worse prognosis in epithelial ovarian cancer, whereas Bcl-2 expression is related to a better outcome. For hormonal status, expression of PR is found to be an independent indicator of favourable prognosis. These results should be supported by more and larger studies., Competing Interests: The authors declare that they have no competing interests.

Purpose: To assess the compensation of total ocular and corneal wavefront aberrations after conventional myopic LASIK., Methods: This study comprised 57 eyes of 57 patients. Total and corneal aberrations were measured preoperatively and 3 months postoperatively using the OPD-Scan (NIDEK Co Ltd) aberrometer. Total and corneal aberrations root-mean-square (RMS) was calculated out to the 6th Zernike order for a 6.0-mm pupil diameter. The percentage increase postoperatively was defined by the ratio of RMS pre- and postoperatively for each corneal and total eye group. The compensation between corneal and internal aberrations for a given aberration group was defined as: (corneal aberration group RMS - total eye aberration group RMS)/corneal aberration group RMS., Results: Postoperatively, higher order aberrations increased by a factor of 1.77+/-1.26 (total) and 2.47+/-2.25 (corneal) (P<.05). Coma aberration increased by a factor of 2.43+/-2.61 (total) and 2.56+/-2.66 (corneal). Spherical aberration increased by a factor of 1.46+/-1.83 (total) and 2.64+/-2.24 (corneal). The values of the ratio of compensation did not change significantly before and after LASIK for individual aberrations (P>.05)., Conclusions: Although myopic LASIK induced significant corneal aberrations, the level of partial compensation of corneal aberrations by internal structures remained unchanged. These results suggest that the previously described emmetropization that is effective during development may also be effective with acquired variations in corneal shape., (Copyright 2010, SLACK Incorporated.)

The purpose of this study was to analysis the clinicopathological features of adenomatoid odontogenic tumour extrafollicular and to discuss the diagnosis pitfull. We present two cases diagnosed and followed at the C.H.U. Habib Bourguiba, Sfax. It is about a 15 year-old boy and a 46 year-old woman who presented gingival swelling. The panoramic radiographs showed in both cases, a radiolucent area affecting teeth 23, 24 and 35 respectively. A computed tomography scan, realized at the second cas, demonstrated an expansile lesion with a sclerotic rim. An exploratory surgical approach was chosen and the final diagnosis was microscopically confirmed to be an extrafollicular variant of adenomatoid odontogenic tumour. The patients were healthy and have not shown any signs of recurrence at follow-up. The two cases described illustrate clinical and radiographic features of the extrafollicular variant of adenomatoid odontogenic tumour. Careful diagnostic procedure and adequate interpretation of radiographic findings may result in a correct diagnosis with otherwise may result in unnecessary endodontic treatment.

Introduction: Rhabdomyosarcoma is the most common soft tissue sarcoma in the first two decades of life. Its most common location is the head and neck. It rarely arises in the thorax including the pleura. There are only 7 previously reported cases in the literature. We report a case of primary pleural rhabdomyosarcoma with an unusual clinical presentation and location. Our aim is to discuss the clinical presentation, treatment and prognosis of this uncommon location of rhabdomyosarcoma., Case Report: We report a case of primary embryonal rhabdomyosarcoma of the pleura in a boy of 21 months. The presentation was characterized by recurrent spontaneous pneumothorax. A computed tomography scan showed only pleural detachment with no evidence of any pleural disease. The malignant cells incidentally found in routine pleural biopsy were the diagnostic clue. The rhabdomyoblastic nature of these cells was confirmed by positive immunostains for myoD1 and desmin. Investigation for metastases was negative. Despite chemotherapy, the tumour quickly increased in size and the infant died from acute respiratory failure., Conclusion: Thoracic rhabdomyosarcoma is rare and remains clinically silent for a long time. Its management is still controversial. Prognosis is generally poor when compared with other locations.

Whereas the interplay of multiple hormones is essential for most plant developmental processes, the key integrating molecular players remain largely undiscovered or uncharacterized. It is shown here that a member of the tomato auxin/indole-3-acetic acid (Aux/IAA) gene family, Sl-IAA3, intersects the auxin and ethylene signal transduction pathways. Aux/IAA genes encode short-lived transcriptional regulators central to the control of auxin responses. Their functions have been defined primarily by dominant, gain-of-function mutant alleles in Arabidopsis. The Sl-IAA3 gene encodes a nuclear-targeted protein that can repress transcription from auxin-responsive promoters. Sl-IAA3 expression is auxin and ethylene dependent, is regulated on a tight tissue-specific basis, and is associated with tissues undergoing differential growth such as in epinastic petioles and apical hook. Antisense down-regulation of Sl-IAA3 results in auxin and ethylene-related phenotypes, including altered apical dominance, lower auxin sensitivity, exaggerated apical hook curvature in the dark and reduced petiole epinasty in the light. The results provide novel insights into the roles of Aux/IAAs and position the Sl-IAA3 protein at the crossroads of auxin and ethylene signalling in tomato.

A 71-year-old man presented with a several year story of a slowly enlarging, painful mass of the knee. Surgical findings showed a subcutaneous, well-circumscribed mass fixed to the patella, and a wide resection was performed. Macroscopically, the tumour measured 6 x 5 x 5 cm and was well circumscribed. The tumour was characterised by superficial location, large size and focal marked atypia. In addition, areas of benign glomus tumour (GT) were identified. The findings appear to be consistent with the diagnosis of GT of uncertain malignant potential.

Congenital cystic adenomatoid malformation (CCAM) of the lung is a rare congenital developmental abnormality, representing about 25% of all congenital lung lesions. In many cases, respiratory distress occurs during the neonatal period, and in about 80- 85% of patients, CCAM is diagnosed before the age of two years due to respiratory infection. It is very rare that presentation is delayed until adulthood. We report three cases of CCAM presenting in adults. The diagnosis was based on clinical and radiological findings in one case and two patients were not diagnosed until surgery. The lesion was present in the right lung in two and in left lung in one patient. All patients underwent surgical resection. The result of histopathological examination confirmed CCAM Stocker type 1, without malignancy. The post operative follow up showed an excellent recovery. Clinicians and pathologists need to be aware of the fact that CCAM can be present for the first time in adolescents or in adults. The clinical diagnosis is suggested by radiographic findings and is confirmed at pathology as surgery is generally indicated.

Mesenchymal hamartoma of the chest wall is a very rare, benign tumour with distinct clinical, radiological and histopathologic characteristics. The lesion develops during foetal life, and is present at or shortly after birth with an extrapleural mass arising from the rib cage with or without respiratory distress and marked rib deformity. Several imaging techniques have been used for diagnosis, but a definitive diagnosis is established only by histopathological examination. Such lesions are composed of a varying admixture of hyaline cartilage that has features resembling growth plate cartilage, along with fascicles of spindle cells, woven bone and hemorrhagic cysts. Accurate diagnosis of mesenchymal hamartoma is important since many chest wall masses in children are malignant. We report a case of mesenchymal hamartoma of the left posterior chest wall surgically resected in an infant who was found to have a palpable mass at birth. Two years after surgery, the patient is alive and well, with no evidence of recurrence.

Purpose: To measure prospectively the early changes in corneal hysteresis, topography, and pachymetry after the creation of a stromal flap cut without laser photoablation., Methods: A 37-year-old man was referred for a bioptic procedure to correct for compound myopic astigmatism in the left eye. A 159-microm-thick 8x8.5-mm superior hinged flap was created with a mechanical microkeratome in the left cornea. Changes in the corneal hysteresis, corneal resistance factor, Goldmann correlated intraocular pressure (lOP), corneal compensated IOP, anterior and posterior topography, and optical and ultrasound pachymetry were monitored prospectively before and at 1 hour, 1 day, 5 days, and 25 days after flap creation. The right eye served as a control., Results: In the left eye, corneal hysteresis and corneal resistance factor decreased immediately after the flap cut and remained lower than preoperatively at 1 hour, 1 day, 5 days, and 25 days. Corneal compensated IOP varied significantly less than Goldmann correlated IOP in both eyes. Central flattening of the horizontal meridians was observed on the difference topography maps. The values of the left eye posterior best fit sphere increased after the flap cut. Increased central corneal thickness occurred immediately after the flap cut and decreased over time without returning to its preoperative value., Conclusions: The creation of a stromal flap can modify the biomechanical properties of the cornea, including a reduction in corneal hysteresis. The topographic changes were consistent with previously reported cases of flap cut in normal corneas.

Aim: A restrospective study was carried in order to evaluate the efficacy and safety of retrobulbar anaesthesia during keratoplasty., Methods: Of 250 consecutive keratoplasty, 30 (12%) were performed under retrobulbar anaesthesia. Patients received a mean volume of 12 ml, composed of etidocaine (2/3), bupicaine (1/3) and hyaluronidase. Ocular compression duration was at least 20 minutes., Results: Surgery was found painless by 90% of patients. Akinesia was complete in 80% of cases., Conclusion: Theses results demonstrate that retrobulbar anaesthesia may be recommended to this type of surgery.

Purpose: To evaluate the efficacy and safety of subconjunctival injections of clindamycin associated with oral corticotherapy in the treatment of toxoplasmic retinochoroiditis (TRC) and its effect on recurrence., Patients and Methods: This study investigated 21 patients (10 males and 11 females) who presented to an ophthalmological department from 1995 to 2000, aged 14-55 years (mean, 28 years), with unilateral TRC. They were treated with subconjunctival injections of clindamycin and systemic corticotherapy at a dose of 1 mg/kg/day. Clinical follow-up consisted of assessment of visual acuity and biomicroscopic fundus examination, completed by retinal angiography if necessary., Results: We observed clinical improvement in 68.75% of patients within 4 days and in all patients healing of the chorioretinal area within 1.6 months. During the follow-up period ranging from 6 to 52 months (mean, 22 months), there have been two recurrences (9%) over the first 18 months. Tolerance of the injections was good. Serious side effects were noted in two patients: one case of conjunctival necrosis and one case of corneal and conjunctival erosion., Conclusion: In treating ocular toxoplasmosis, clindamycin appears to be a safe and effective substitute for the classic protocol (pyrimethamine-sulfadiazine, pyrimethamine-azithromycin), for which a 50% recurrence rate has been reported. It provides relatively good protection against recurrence and warrants testing in further controlled studies.

Auxin/indole-3-acetic acid (Aux/IAA) proteins are transcriptional regulators that mediate many aspects of plant responses to auxin. While functions of most Aux/IAAs have been defined mainly by gain-of-function mutant alleles in Arabidopsis thaliana, phenotypes associated with loss-of-function mutations have been scarce and subtle. We report here that the downregulation of IAA9, a tomato (Solanum lycopersicum) gene from a distinct subfamily of Aux/IAA genes, results in a pleiotropic phenotype, consistent with its ubiquitous expression pattern. IAA9-inhibited lines have simple leaves instead of wild-type compound leaves, and fruit development is triggered before fertilization, giving rise to parthenocarpy. This indicates that IAA9 is a key mediator of leaf morphogenesis and fruit set. In addition, antisense plants displayed auxin-related growth alterations, including enhanced hypocotyl/stem elongation, increased leaf vascularization, and reduced apical dominance. Auxin dose-response assays revealed that IAA9 downregulated lines were hypersensitive to auxin, although the only early auxin-responsive gene that was found to be upregulated in the antisense lines was IAA3. The activity of the IAA3 promoter was stimulated in the IAA9 antisense genetic background, indicating that IAA9 acts in planta as a transcriptional repressor of auxin signaling. While no mutation in any member of subfamily IV has been reported to date, the phenotypes associated with the downregulation of IAA9 reveal distinct and novel roles for members of the Aux/IAA gene family.

Objective: Testicular differentiation can occur in the absence of the Y chromosome giving XX sex-reversed males. Although Y chromosomal sequences can be detected in the majority of male subjects with a 46,XX karyotype, several studies have shown that approximately 10% of patients lack Y material including the SRY gene. The aim of this study was to see if the classification of XX sex-reversed individuals into three groups, Y-DNA-positive phenotypically normal XX males, Y-DNA-negative XX males with genital ambiguities and Y-DNA-negative true hermaphrodites can be applied to our cases., Design: Endocrinological and genetic studies were conducted in 20 XX sex-reversed patients., Patients: Twenty patients with various phenotypes were studied. They were between 20 days and 35 years old. Ten presented ambiguous external genitalia (Prader's stages II to IV). After laparotomy or gonadal biopsy, the diagnosis was 46,XX true hermaphroditism in five, and XX male in 15., Measurements: Blood samples were obtained from all patients for hormonal and molecular studies. Basal levels of testosterone, oestradiol and pituitary gonadotrophins were measured by RIA. In addition, two stimulation tests were performed: gonadotrophin stimulation with GnRH and testicular stimulation with hCG. Several Y-specific DNA sequences of the short arm of the Y chromosome were analysed by Southern blot and polymerase chain reaction methods., Results: In this study, three categories of XX sex-reversed individuals were observed: phenotypically normal males with or without gynaecomastia, males with genital ambiguities, and true hermaphrodites. Endocrinological data were similar in XX males and in true hermaphrodites. Testosterone levels exhibited normal (n = 9) or decreased (n = 11) values. The hCG response was low. FSH and LH were elevated in 13 patients. Molecular analysis in ten patients showed varying amounts of Y material including the Y boundary and SRY. Ten patients with various phenotypes lacked Y chromosomal DNA. There was no relation between Leydig cell function (as indicated by testosterone levels before or after hCG stimulation) and the presence of Y chromosome material., Conclusion: Although the presence of Y-specific DNA generally results in a more masculinized phenotype, exceptions do occur. In the Y-DNA-negative group, complete or incomplete masculinization in the absence of SRY suggests a mutation of one or more downstream non-Y, testis-determining genes.

During mammalian embryogenesis, the presence of the SRY gene determines the bipotential gonad to develop as a testis. 46,XY sex reversal has been described in man. It is associated with an essentially female phenotype and a streak gonad. In a collaborative study, we analysed 36 patients with a 46,XY sex reversal. The testis determining region of the Y chromosome was analysed by Southern blotting and by DGGE analysis of the SRY open reading frame (orf). We found a total of 7 mutations in the testis determining region including the SRY gene. This brings to 19 the total number of mutations in SRY associated with sex reversal. No relationship was found between the SRY status and the presence or absence of gonadoblastoma. However, a correlation was observed between the SRY genotype and the histology of the gonad. A mutant in SRY is associated with a completely dysgenetic gonad. The presence of immature testicular tubules is usually observed when SRY is normal. These latter results suggest the existence of as yet unidentified testis determining genes.