Selective method for identification and quantification of Bifidobacterium animalis subspecies lactis BB-12 (BB-12) from the gastrointestinal tract of healthy volunteers ingesting a combination probiotic of BB-12 and Lactobacillus rhamnosus GG.

AIM: To develop a novel validated method for the isolation of Bifidobacterium animalis ssp. lactis BB-12 (BB-12) from faecal specimens and apply it to studies of BB-12 and Lactobacillus rhamnosus GG (LGG) recovered from the healthy human gastrointestinal (GI) tract. METHODS AND RESULTS: A novel method for isolating and enumerating BB-12 was developed based on its morphologic features of growth on tetracycline-containing agar. The method identified BB-12 correctly from spiked stool close to 100% of the time as validated by PCR confirmation of identity, and resulted in 97-104% recovery of BB-12. The method was then applied in a study of the recovery of BB-12 and LGG from the GI tract of healthy humans consuming ProNutrients® Probiotic powder sachet containing BB-12 and LGG. Viable BB-12 and LGG were recovered from stool after 21 days of probiotic ingestion compared to baseline. In contrast, no organisms were recovered 21 days after baseline in the nonsupplemented control group. CONCLUSIONS: We demonstrated recovery of viable BB-12, using a validated novel method specific for the isolation of BB-12, and LGG from the GI tract of healthy humans who consumed the probiotic supplement. SIGNIFICANCE AND IMPACT OF THE STUDY: This method will enable more detailed and specific studies of BB-12 in probiotic supplements, including when in combination with LGG.

Mineralocorticoid effects due to cortisol inactivation overload explain the beneficial use of hydrocortisone in septic shock.

The role of corticosteroids in septic shock remains controversial despite their use for over 50 years. Large prospective trials of their use continue with the aim of resolving the controversy. These may well remain indecisive if basic endocrine principles are ignored. Review of the available evidence suggests that use of synthetic glucocorticoids is harmful but hydrocortisone beneficial. Consideration of the basic properties of the corticosteroids used and their receptors suggest an explanation for their differing therapeutic effects. The harmful synthetic glucocorticoids have no or reduced mineralocorticoid effects in contrast with the significant mineralocorticoid effects of hydrocortisone at the doses which have been found to be beneficial. The potent synthetic mineralocorticoid fludrocortisone is well recognised to raise peripheral resistance by sensitising the resistance vessels to endogenous or exogenous catecholamines and also causes metabolic alkalosis. We provide evidence to support our hypothesis that at the doses of hydrocortisone used, cortisol inactivation overload is the basis of the beneficial effect. The consequent mineralocorticoid effects result in increased sensitivity of the resistance vessels to endogenous and exogenous catecholamines with an increase in peripheral resistance correcting shock. In addition the metabolic alkalotic component of mineralocorticoid effect would tend to correct the prevailing metabolic acidosis. Hydrocortisone also has an attenuating, as opposed to the suppressing effect of synthetic glucocorticoids on the immune response which is also regarded as beneficial.

Major histocompatibility complex and T cell receptor interaction of the P91A tum- peptide.

The P91A antigen was identified following mutation of P1 mastocytoma cells. The peptide epitope is encoded by a mutant form of the S3 subunit of the PA700 proteasome regulatory complex. P91A stimulates a strong CD8+ T cell response when expressed on tumor cells or normal tissue and P91A-specific T cells express a restricted range of T cell receptors. Although it is a strong Ld-binding peptide, P91A does not conform to the established motif for this major histocompatibility complex (MHC) molecule and this has hampered elucidation of the precise epitope. Ld predominantly associates with nonamer peptides; however, using a variety of complementary approaches, the P91A epitope is identified as the octamer QNHRALDL. In the absence of the Ld motif residue proline at position 2, residues 5-7 are primarily involved in MHC interaction. P91A is thus atypical in its interaction with Ld. Residues 1, 3, and 4 are found to influence T cell recognition of P91A. Definition of the P91A peptide will allow studies on P91A processing and interactions of the P91A peptide/MHC complex with T cell receptors of differing avidity to establish the basis for restricted T cell receptor usage. The basis for the failure of the P91A tum+ peptide (QNRRALDL) to bind to Ld is addressed by molecular modeling.

Intrarectal tear from water skiing.

We report a case of intrarectal tear and hemorrhage after a fall while water skiing. The injury resulted from rectal douche, or jet enema, which is dangerous because of the high pressure of the water jets forced into the rectum. The patient, a middle-aged woman, had colonoscopy, which revealed a deep rectal laceration. During subsequent colostomy, a full-thickness laceration and an extensive pelvic and retroperitoneal hematoma with some free blood were found. The patient's recovery was uneventful, and she subsequently had reanastomosis of her colostomy. We recommend protective apparel to prevent these injuries.

Intractable epilepsy.

A 26-year-old female had her first partial seizure at the age of five years. Further seizures occurred and later became generalised in nature. Control of the seizures became difficult despite the use of nine different anticonvulsants over a period of 20 years. She was not suitable for neurosurgical intervention because of the diffuse nature of her seizures. Cerebellar stimulation had only a marginal effect on seizure frequency. With time she became mentally retarded and was unable to benefit from formal education. Her illness demonstrates many of the long-term clinical features and management problems of intractable epilepsy.

Detection of carcinoma of the colon and rectum by air contrast enema.

In a retrospective review of 55 patients with carcinoma of the colon and rectum, air contrast enema detected 91 per cent of the Dukes' A and B lesions and 96 per cent of the Dukes' C and D lesions. This roentgenographic method is an effective diagnostic tool for use at all colorectal levels, including the rectum. Results suggest that the initial work-up of patients suspected o harboring early carcinoma of the colon and rectum can be done by air contrast enema and rigid proctosigmoidoscopic examination with reasonable detection accuracy. Controlled studies comparing these methods with routine flexible endoscopic examination are needed.