Existence of a pool of T-lymphocyte colony-forming cells (T-CFC) in human bone marrow and their place in the differentiation of the T- lymphocyte lineage

The existence and characteristics of bone marrow T-cell progenitors have not yet been established in man. Several pieces of evidence such as the reconstitution of certain immunodeficiencies by bone marrow graft suggest that T-cell precursors are present in the bone marrow. We report the growth of T-cell colonies from bone marrow populations using PHA-stimulated lymphocyte-conditioned medium containing T-cell growth factor (TCGF). Rosetting experiments and complement-dependent cytotoxicity assays with monoclonal antibodies indicate that the bone marrow T colony-forming cells (T-CFC) are E- OKT 3- and la+, i.e., immature progenitors. The colonies derived from these cells have the phenotype of mature T cells: E + OKT 3 + la- with either helper (OKT 4+) and suppressor (OKT 8 +) antigens. These results suggest that a thymic microenvironment may not be necessary for the in vitro proliferation and differentiation of the T-cell lineage in adult humans. These methodologies may permit direct investigation of early phenomena concerning the T-cell lineage, such as the acquisition of self-tolerance, the formation of a repertoire of specificities, and the HLA restriction phenomena that we believe takes place before the thymic maturation.     

Pressure erosions of bone in rheumatoid arthritis: a subject review

Pressure, or compressive, erosions of bone in various locations in patients with rheumatoid arthritis are described. Possible pathophysiologic mechanisms that account for the appearance and distribution of these erosions include osteopenia, soft-tissue laxity, soft-tissue pressure on bone, bone pressure on bone, and muscular forces.     

Breast specimen radiography: evaluation of a compression device

The irregular shape and uneven tissue thickness of excised breast specimens makes radiographic evaluation difficult, especially when calcifications are not present. Xeroradiographs before and after compression of 20 separate excised breast specimens were compared, and 17 of the same specimens were compared after compression combined with immersion in water. Specimen compression improved visibility of the lesion on average in 88% of cases, and visibility was equal in 12%. Combined compression/immersion further improved visibility of the lesion on average in 37% of cases. More significantly, evaluation of the compressed specimen led to a change in interpretation of the radiographs in 45% of cases. Compression of the specimen in specimen radiography is recommended in all cases in which pre-biopsy localization is performed.     

A longitudinal immunologic evaluation of hemophiliac patients

Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity.     

Endoluminal procedures for bariatric patients: expectations among bariatric surgeons

BackgroundPrimary and revisional bariatric endoluminal procedures are currently being developed. Acceptable levels of risk and weight loss for these procedures have not yet been established. The aim of this study was to evaluate the expectations and concerns among bariatric surgeons regarding these procedures.MethodsThe American Society for Metabolic and Bariatric Surgery Emerging Technologies Committee developed a questionnaire that was distributed to the membership. Risk tolerance was assessed with comparison to commonly performed endoscopic and bariatric procedures. The percentage of excess weight loss (EWL) ranges were provided to assess the expectations for results 1 year after the procedure.ResultsA total of 214 responses were returned. The acceptable level of risk to achieve 10–20% EWL after primary and revisional procedures was equivalent to, or less than, that of a therapeutic endoscopic procedure for 81% and 76% of respondents, respectively. The acceptable level of risk to achieve 30–40% EWL after primary and revisional procedures was equivalent to that after laparoscopic adjustable gastric banding for 45% and 35% of respondents, respectively and equivalent to that after laparoscopic Roux-en-Y gastric bypass for 8% and 22%, respectively. In addition, 62% of respondents responded that 10–30% EWL would be acceptable for revisional procedures, and 35% responded that 10–30% EWL would be acceptable after a primary procedure. The primary concern was unproven efficacy, followed by durability, poor weight loss, availability of equipment, and procedural risk. Finally, 58% would not be willing to recommend an endoluminal procedure until the efficacy has been established, regardless of the risk.ConclusionRisk tolerance and weight loss expectations among bariatric surgeons are different for primary and revisional endoscopic procedures. Most surgeons were unwilling to consider endoluminal procedures for their patients until the efficacy has been proven.     

肥胖与青少年多囊卵巢综合征

多囊卵巢综合征（PCOS）是育龄妇女常见生殖内分泌疾病。近年发现,随着儿童肥胖患病率增加,青少年PCOS发病率也逐年提高。肥胖可通过增加外周循环胰岛素水平影响PCOS发病机制,PCOS患者高雄激素血症也会增加内脏脂肪沉积。肥胖会增加与PCOS相关的代谢和心血管方面的并发症的患病风险,如胰岛素抵抗（IR）、高脂血症、高血压以及临床症状不明显的动脉粥样硬化等。早期识别青春期PCOS,有利于及时纠正、阻断其内分泌紊乱,防止近期及远期并发症发生。