Characteristics of acute groin injuries in the adductor muscles: A detailed MRI study in athletes.

Acute adductor injuries account for the majority of acute groin injuries; however, little is known about specific injury characteristics, which could be important for the understanding of etiology and management of these injuries. The study aim was to describe acute adductor injuries in athletes using magnetic resonance imaging (MRI). Male athletes with acute groin pain and an MRI confirmed acute adductor muscle injury were prospectively included. MRI was performed within 7 days of injury using a standardized protocol and a reliable assessment approach. 156 athletes presented with acute groin pain of which 71 athletes were included, median age 27 years (range 18-37). There were 46 isolated muscle injuries and 25 athletes with multiple adductor injuries. In total, 111 acute adductor muscle injuries were recorded; 62 adductor longus, 18 adductor brevis, 17 pectineus, 9 obturator externus, 4 gracilis, and 1 adductor magnus injury. Adductor longus injuries occurred at three main injury locations; proximal insertion (26%), intramuscular musculo-tendinous junction (MTJ) of the proximal tendon (26%) and the MTJ of the distal tendon (37%). Intramuscular tendon injury was seen in one case. At the proximal insertion, 12 of 16 injuries were complete avulsions. This study shows that acute adductor injuries generally occur in isolation from other muscle groups. Adductor longus is the most frequently injured muscle in isolation and in combination with other adductor muscle injuries. Three characteristic adductor longus injury locations were observed on MRI, with avulsion injuries accounting for three-quarters of injuries at the proximal insertion, and intramuscular tendon injury was uncommon.

Characteristics of acute groin injuries in the hip flexor muscles - a detailed MRI study in athletes.

Hip flexor injuries account for one-third of acute groin injuries; however, little is known about specific injury characteristics. The aims of this study were to describe acute hip flexor injuries using magnetic resonance imaging (MRI) in athletes with acute groin pain and to compare specific muscle injuries with reported injury situations. Male athletes with acute groin pain were prospectively and consecutively included during three sports seasons. MRI was performed within 7 days of injury using a standardized protocol and a reliable assessment approach. All athletes with an MRI confirmed acute hip flexor muscle injury were included. A total of 156 athletes presented with acute groin pain of which 33 athletes were included, median age 26 years (range 18-35). There were 16 rectus femoris, 12 iliacus, 7 psoas major, 4 sartorius, and 1 tensor fascia latae injury. Rectus femoris injuries primarily occurred during kicking (10) and sprinting (4), whereas iliacus injuries most frequently occurred during change of direction (5). In 10 (63%) rectus femoris injuries, tendinous injury was observed. The iliacus and psoas major injuries were mainly observed at the musculotendinous junction (MTJ), and two included tendinous injury. We have illustrated specific injury locations within these muscles, which may be relevant for the clinical diagnosis and prognosis of these injuries. Most proximal rectus femoris injuries included tendinous injury. In contrast, distinct acute iliacus and psoas injuries predominantly occurred at the MTJ. Only the iliacus or psoas major were injured during change of direction, whereas rectus femoris injuries occurred primarily during kicking and sprinting.

Bothrops protease A, a unique highly glycosylated serine proteinase, is a potent, specific fibrinogenolytic agent.

BACKGROUND: The hemostatic system is the major target of snake venom serine proteinases (SVSPs) that act on substrates of the coagulation, fibrinolytic and kallikrein-kinin systems. Bothrops protease A (BPA), the most glycosylated SVSP, is a non-coagulant, thermostable enzyme. A cDNA encoding BPA showed that the protein has a calculated molecular mass of 25 409 Da, implying that approximately 62% of its molecular mass as assessed by sodium dodecylsulfate polyacrylamide gel electrophoresis (67 kDa) is due to carbohydrate moieties. RESULTS: Here we show that BPA is a potent fibrinogenolytic agent in vitro, as it readily degraded human and rat fibrinogen at a very low enzyme concentration. Partially N-deglycosylated BPA (p-N-d-BPA) generated similar fibrinogen products, but with enhanced fibrinogenolytic activity. In vivo, injection of 0.75 nmoles of BPA in rats completely avoided thrombus formation induced by stasis in the vena cava, or by endothelium injury in the jugular vein. Moreover, it decreased the fibrinogen plasma level and prolonged the recalcification time. Cleavage of fibrinogen in human and rat plasma was observed with native BPA and p-N-d-BPA by electrophoresis followed by western blot using an anti-fibrinogen antibody. BPA did not cause unspecific degradation of plasma proteins and did not cleave isolated albumin, vitronectin and fibronectin at the same concentration used with fibrinogen. Serine proteinase inhibitors failed to inhibit BPA, probably due to steric hindrance caused by its huge carbohydrate moieties. CONCLUSIONS: To the best of our knowledge, this investigation underscores a new, thermostable, specific defibrinogenating agent that may have an application in the prevention of thrombus formation.

Immunological parameters of visceral leishmaniasis of Leishmania major-infected golden hamsters.

We can consider the Leishmania major-infected hamster as an interesting model of visceral leishmaniasis. Every hamster infected with L. major strain 70 by peritoneal route developed visceral dissemination of the parasite. When immunological parameters were considered, we saw data quite similar to those presented by visceral leishmaniasis patients: negative leishmanin skin test and presence of anti-leishmania antibody. Histopathological analysis showed dissemination of the parasite mainly to liver and spleen. The former organ showed hypertrophy and hyperplasia of Kupffer cells with focal areas of inflammatory infiltration in nodular pattern. The spleen disclosed intense proliferation and enlargement of mononuclear phagocytic cells, sometimes revealing nodular configuration. Anti-leishmania antibodies were easily detected by indirect immunofluorescent technique in this model. Immunomodulation by Cyclophosphamide decreased the anti-leishmania antibody and delayed-type hypersensitivity test results suggested that hamster was able to develop reaction to leishmania antigen, although leishmanin skin test was negative in the L. major-infected animals. We consider the L. major-infected hamster a useful model for visceral leishmaniasis study because of the similarity of immunological reactions to parasite antigen in human disease.

Cardiovascular involvement in human and experimental leptospirosis: pathologic findings and immunohistochemical detection of leptospiral antigen.

Twenty hearts from patients dying of leptospirosis were studied. Interstitial myocarditis was found in 50% of the cases, and a significant statistical correlation was observed between myocarditis and the inflammatory involvement of the conduction tissue. Acute coronary arteritis, affecting the main branches of the coronary arteries, was observed in 70% of the cases, and this finding also correlates significantly with interstitial myocarditis. Aortitis was found in 57.8% of the cases. When serum against L. interrogans serovar icterohaemorrhagiae was used, focal IP antigen deposits were observed in the coronary arteries and in the aorta. Experimental data from 12 guinea-pigs inoculated with L. interrogans serovar icterohaemorrhagiae showed a focal myocarditis involving mainly the subendocardial and pericoronary heart tissue, with IP antigen deposits in the same sites. Leptospirosis might be visualized as a generalized illness resembling other infectious vasculitides. The heart and main vessels are involved during the septicaemic phase of the disease, and bacterial migration, toxin(s), enzymes and/or antigenic products liberated by bacterial lysis might account for the increased endothelial permeability with antigen deposits and inflammation.

Experimental leptospirosis (L. interrogans serovar icterohaemorrhagiae) of the guinea pig: leptospiral antigen, gamma globulin and complement C3 detection in the kidney.

Morphofunctional and immunofluorescent studies were done in guinea pigs experimentally infected with Leptospira interrogans serovar icterohaemorrhagiae to determine the role of leptospiral antigen, gamma-globulin, and complement C3 deposits in the pathogenesis of the renal lesions. A sharp increase in leptospiral antigen deposits was observed in the late phase of the experimental infection. Immunoglobulin and complement C3 were small compared with the heavy leptospiral antigen deposits. Moreover, leptospiral antigen was observed mainly in the interstitium whereas immunoglobulin and complement C3 deposits were seen in glomeruli and small blood vessel walls. In our experimental model bacterial migration and local liberation of factors causing virulence seems more likely to determine the renal damage.

Chronic human schistosomiasis mansoni-schistosomal antigen, immunoglobulins and complement C3 detection in the liver.

The distribution of schistosomal antigen, immunoglobulins and complement C3 was studied by IF stain in 26 biopsies of human liver from 21 cases of hepatosplenic and five of intestinal schistosomiasis mansoni. Schistosomal antigen and immunoglobulins, chiefly of the IgG class and in a lesser intensity complement C3, were seen focally as scanty deposits in cells of the sinusoidal wall. They probably correspond to antigen-antibody insoluble large aggregates which are being removed by local cells of the mononuclear phagocyte system. Gamma globulin of the IgG class and antigens were also present in the granuloma around S. mansoni eggs and dead worms in the human liver. During the early phase of the granulomatous reaction the structure was not efficient enough to wall off completely the antigen, which is seen in cells at the center of the granuloma. As the granuloma matures, antigen demonstration becomes restricted to the miracidium, and immunoglobulins are observed mainly at the periphery. The kinetics of the granuloma formation with intralesional antibody presence promote a progressive antigen neutralization.