Extracellular matrix molecules as targets for brown spider venom toxins

Loxoscelism, the term used to describe lesions and clinical manifestations induced by brown spider's venom (Loxosceles genus), has attracted much attention over the last years. Brown spider bites have been reported to cause a local and acute inflammatory reaction that may evolve to dermonecrosis (a hallmark of envenomation) and hemorrhage at the bite site, besides systemic manifestations such as thrombocytopenia, disseminated intravascular coagulation, hemolysis, and renal failure. The molecular mechanisms by which Loxosceles venoms induce injury are currently under investigation. In this review, we focused on the latest reports describing the biological and physiopathological aspects of loxoscelism, with reference mainly to the proteases recently described as metalloproteases and serine proteases, as well as on the proteolytic effects triggered by L. intermedia venom upon extracellular matrix constituents such as fibronectin, fibrinogen, entactin and heparan sulfate proteoglycan, besides the disruptive activity of the venom on Engelbreth-Holm-Swarm basement membranes. Degradation of these extracellular matrix molecules and the observed disruption of basement membranes could be related to deleterious activities of the venom such as loss of vessel and glomerular integrity and spreading of the venom toxins to underlying tissues.

Development and evaluation of the neutralizing capacity of horse antivenom against the Brazilian spider Loxosceles intermedia

Spider bites due to Loxosceles intermedia are currently a major public health problem in South Brazil. About 3000 cases are reported annually. Specific treatment for spider bites is provided by the polyvalent anti-arachnidic antiserum produced by Butantan Institute, São Paulo, Brazil by immunizing horses with mixtures of venoms from Tityus serrulatus and T. bahiensis scorpions, as well as Phoneutria nigriventer and L. gaucho spiders. Due to the large amounts of the anti-arachnidic antivenom required and since L. intermedia venom has some biochemical and pharmacological variations, we have produced a specific anti-L. intermedia antivenom. This study shows that horses immunized with crude L. intermedia venom produced IgG antibodies that neutralized the dermonecrotic and lethal activities of the venom. The neutralizing potency of the anti-loxoscelic antivenom was compared with that of the anti-arachnidic antivenom. Our results indicate that both antivenoms were effective in terms of neutralization. However, the anti-loxoscelic antivenom was more efficient than the anti-arachnidic.

Posterior sagittal transanorectal approach in patients with ambiguous genitalia: report of eight cases

The posterior sagittal transanorectal approach was used for reconstruction of the female genitalia (vaginoplasty) in eight girls with urogenital sinus, high vaginal implantation, and normal rectum, in all cases with a protective sigmoidostomy. These eight patients included four female and four male pseudohermaphrodites. They remain fecally continent, but only seven have urinary continence. One girl has a neuropathic bladder: umbilical discomfort during abdominal straining is present in one patient. One girl married and demonstrated satisfactory sexual intercourse. All patients are alive and healthy, physically and mentally. The transanorectal approach allows separation of the vagina from the urethra and bladder, provides good vaginal mobilization down to the perineum, avoids the utilization of perineal skin flaps and sometimes a laparotomy, and preserves defecation and urinary control. The cosmetic appearance of the genitalia seems to be better than that achieved in the past with other techniques.

Transsphinctericanorectal reconstruction of ambiguous genitalia: an innovative approach to neovaginoplasty, pioneer in Brazil

The authors, based upon previous experience in the treatment of ten children with cloacal abnormalities, among which two with female pseudohermaphroditism with cloaca, hereby present a pioneer experience in Brazil, with the "posterior sagittal transsphinctericanorectalurethrovaginoplasty" a surgical approach to neovaginoplasty described by "Cripps/Peña", which was utilized for the reconstruction of the genitalia of three intersexuated adolescents with protective colostomy, who presented an urogenital sinus, high vaginal implantation and a normal rectum. One patient was an adrenal female pseudohermaphrodite and two were male pseudohermaphrodites. The authors present a brief report on the three cases, describe the surgical procedure, relate on the anatomy of the urogenital sinus and discuss surgical indications, diagnosis and results, comparing them to the reviewed international literature.

Testicular regression in a patient with virilized female phenotype

The 16-year old girl studied here had ambiguous external genitalia, ie, enlarged clitoris, pseudo vagina, and rudiments of Wolffian tubes. Her karyotype was 46,XY and she was H-Y antigen-positive. In spite of absence of gonadal tissue, genital virilization suggests presence of testes during embryogenesis. This patient is compared to 20 others with testicular regression from the literature. Autosomal-recessive inheritance of this condition is proposed.