Effects of dietary supplementation of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens.

Plant polyphenols, especially flavonoids, are of great interest due to their wide range of biological activities. Quercetin, a ubiquitous flavonoid, is known to have antioxidant and antibacterial effects. In this study, we investigated the effect of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens. Two hundred forty 28-wk-old Hessian laying hens, with an average laying rate of lay 85% at the start, were randomly allotted to 4 treatments and fed 1 of 4 diets (negative control, 0.2, 0.4, and 0.6 g of quercetin/kg of diet) for 8 wk. Layer performance responses, egg quality parameters, cecal microflora populations and antioxidant status were measured at the end of the experiment. Results showed that feed conversion decreased as the quercetin level increased. Laying rate had a quadratic correlation with the level of quercetin (P = 0.056) and was maximized by the supplementation level of 0.2 g/kg of diet. However, no significant quercetin effect was observed on egg quality. Regression analysis showed that the population of total aerobes and coliforms decreased and the population of Bifidobacteria increased as the level of quercetin increased. Regression analysis also showed the activities of Cu-Zn-superoxide dismutase increased as the level of quercetin increased (P < 0.05). Results of the study suggest that the appropriate level of supplementation is 0.367 to 0.369 g of quercetin/kg of feed based on the improvement of laying rate (with 88.55 as maximum value) and feed conversion (with 2.0725 as minimum value). Our observations provided further evidence that dietary supplementation of quercetin improved performance by modulation of intestinal environment and liver superoxide dismutase content in laying hens. Quercetin has the potential as functional feed additive in animal production.

Efficacy of fasting and calorie restriction (FCR) on mood and depression among ageing men.

OBJECTIVE: An intervention study on the FCR (Fasting and Calorie Restriction) dietary regime was carried out to determine its efficacy in improving mood states and depression status among ageing men. SUBJECTS: A total of 32 healthy males (Mean±SD), aged 59.7±6.3 years, with a BMI of 26.7±2.2 kg/m2 were recruited to the study. METHOD: Participants were randomized to either the FCR group (and were instructed to follow a calorie restricted dietary regime with intermittent fasting) or to the control group (in which individuals were asked to maintain their current lifestyle), for a 3 month period. Mood was assessed using the Profile of Mood States and depression was assessed using Beck Depression Inventory-II and Geriatric Depression Scale-15 at baseline, week 6 and week 12 of the intervention. RESULTS: A total of 31 subjects completed the study (n=16, FCR and n=15, control). Significant decreases in tension, anger, confusion and total mood disturbance and improvements in vigor were observed in participants in the FCR group compared to the control group (p<0.05). No significant changes in mean depression scores were observed. Weight, BMI and percent body fat were reduced by 3.8%, 3.7% and 5.7% respectively in the FCR group. CONCLUSIONS: Our findings show that a FCR dietary regime is effective in improving mood states and nutritional status among ageing men.

The structure and roles of sterile flowers in Viburnum macrocephalum f. keteleeri (Adoxaceae).

The formation and ecological roles of sterile flowers in flowering plants are interesting issues in floral biology and evolution. Here, we investigated the morphological and anatomical characteristics of both fertile and sterile flowers of Viburnum macrocephalum f. keteleeri, a self-incompatible and insect-pollinated shrub, during different developmental stages of flowers. In addition, pollinator visitation rates and fruit set were determined in intact inflorescences and those with sterile flowers removed. The results indicate that sterile and fertile flowers were developmentally similar during early developmental stages, and that development of the flower types diverged about 15 days before flowering. In addition, pollinator visitation rates, number of pollen grains on stigmas and fruit set were significantly higher in inflorescences with sterile flowers than those without sterile flowers. The results suggest that sterile flowers of this species evolved from fertile flowers under long-term selective pressure, and play a crucial role in enhancing reproductive success through effectively attracting pollinators to the plant and thus enhancing fruit set.

Detection of the furcation involvement of a multi-rooted molar using natural frequency analysis: a numerical approach.

The aim of this study was to evaluate the potential for using the natural frequency (NF) as a parameter to detect vertical bone loss at the furcation of human molars as well as to assess the role that the surrounding bone plays in maintaining molar stability. A three-dimensional finite element model of the human maxillary molar was built. The NF values of the molar modal were calculated with one-sided, two-sided, and three-sided vertical bone loss. It was found that the change in the NF was less than 25 per cent in molars with a one-sided defect when the bone level varied by 10 mm from the cementoenamel junction. However, when a three-sided bony defect was simulated, the change in the NF ranged from 40 to 60 per cent. In addition, it was found that bone loss that had reached the furcation entrance (4 mm) resulted in a sharp change in the NF value. Furthermore, it was found that bone loss involving the mesial and distal surfaces resulted in a larger decrease in the NF value compared with bone loss involving the buccal and palatal surfaces. These results demonstrated that the bone surrounding the mesial and distal sides plays a more important role in maintaining molar stability than does the bone surrounding the buccal and palatal sides.

Natural frequency analysis of tooth stability under various simulated types and degrees of alveolar vertical bone loss.

The aim of this study was to test natural teeth stability under various simulated types and degrees of alveolar vertical bone loss, as well as to assess the role that the surrounding bone played for maintaining tooth stability. A three-dimensional finite element model of the human maxillary central incisor with surrounding tissue, including periodontal ligament, enamel, dentin, pulp, and alveolar bone, was established. One side and multiple vertical bone loss were simulated by means of decreasing the surrounding bone level apically from the cemento-enamel junction in 1 mm steps incrementally downward for 10 mm. Natural frequency values of the incisor model with various types and degrees of bone loss were then calculated. The results showed that, with one-sided bone resorption, the model with labial bone loss had the lowest natural frequency decreasing rates (8.2 per cent). On the other hand, in cases of multiple bone loss, vertical bone resorption at the mesial and distal sides had more negative effects on tooth stability compared to vertical bone losses on facial and lingual sides. These findings suggest that the natural frequency method may be a useful, auxiliary clinical tool for diagnosis of vertical periodontal diseases.

The potential therapeutic role of lymph node resection in epithelial ovarian cancer: a study of 13918 patients.

The aim of the study is to determine the role of lymphadenectomy in advanced epithelial ovarian cancer. The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program reported between 1988 and 2001. Kaplan-Meier estimates and Cox proportional hazards regression models were used for analysis. Of 13 918 women with stage III-IV epithelial ovarian cancer (median age: 64 years), 87.9% were Caucasian, 5.6% African Americans, and 4.4% Asians. A total of 4260 (30.6%) underwent lymph node dissections with a median number of six nodes reported. For all patients, a more extensive lymph node dissection (0, 1, 2-5, 6-10, 11-20, and >20 nodes) was associated with an improved 5-year disease-specific survival of 26.1, 35.2, 42.6, 48.4, 47.5, and 47.8%, respectively (P<0.001). Of the stage IIIC patients with nodal metastases, the extent of nodal resection (1, 2-5, 6-10, 11-20, and >20 nodes) was associated with improved survivals of 36.9, 45.0, 47.8, 48.7, and 51.1%, respectively (P=0.023). On multivariate analysis, the extent of lymph node dissection and number of positive nodes were significant independent prognosticators after adjusting for age, year at diagnosis, stage, and grade of disease. The extent of lymphadenectomy is associated with an improved disease-specific survival of women with advanced epithelial ovarian cancer.

Ovarian cancer in younger vs older women: a population-based analysis.

To compare the clinico-pathologic prognostic factors and survival of younger vs older women diagnosed with epithelial ovarian cancer. Demographic, clinico-pathologic, treatment, and surgery information were obtained from patients with ovarian cancer from the Surveillance, Epidemiology, and End Results Program from 1988 to 2001 and analysed using Kaplan-Meier estimates. Of 28 165 patients, 400 were <30 years (very young), 11 601 were 30-60 (young), and 16 164 were >60 (older) years of age. Of the very young, young, and older patients, 261 (65.3%), 4664 (40.2%), and 3643 (22.5%) had stage I-II disease, respectively (P<0.001). Across all stages, very young women had a significant survival advantage over the young and older groups with 5-year disease-specific survival estimates at 78.8% vs 58.8 and 35.3%, respectively (P<0.001). This survival difference between the age groups persists even after adjusting for race, stage, grade, and surgical treatment. Reproductive age (16-40 years) women with stage I-II epithelial ovarian cancer who received uterine-sparing procedures had similar survivals compared to those who underwent standard surgery (93.3% vs 91.5%, P=0.26). Younger women with epithelial ovarian cancer have a survival advantage compared to older patients.

Uterine papillary serous and clear cell carcinomas predict for poorer survival compared to grade 3 endometrioid corpus cancers.

To compare the survival of women with uterine papillary serous carcinoma (UPSC) and clear cell carcinoma (CC) to those with grade 3 endometrioid uterine carcinoma (G3EC). Demographic, pathologic, treatment, and survival information were obtained from the Surveillance, Epidemiology, and End Results Program from 1988 to 2001. Data were analysed using Kaplan-Meier and Cox proportional hazards regression methods. Of 4180 women, 1473 had UPSC, 391 had CC, and 2316 had G3EC cancers. Uterine papillary serous carcinoma and CC patients were older (median age: 70 years and 68 vs 66 years, respectively; P<0.0001) and more likely to be black compared to G3EC (15 and 12% vs 7%; P<0.0001). A higher proportion of UPSC and CC patients had stage III-IV disease compared to G3EC patients (52 and 36% vs 29%; P<0.0001). Uterine papillary serous carcinoma, CC and G3EC patients represent 10, 3, and 15% of endometrial cancers but account for 39, 8, and 27% of cancer deaths, respectively. The 5-year disease-specific survivals for women with UPSC, CC and G3EC were 55, 68, and 77%, respectively (P<0.0001). The survival differences between UPSC, CC and G3EC persist after controlling for stage I-II (74, 82, and 86%; P<0.0001) and stage III-IV disease (33, 40, and 54; P<0.0001). On multivariate analysis, more favourable histology (G3EC), younger age, and earlier stage were independent predictors of improved survival. Women with UPSC and CC of the uterus have a significantly poorer prognosis compared to those with G3EC. These findings should be considered in the counselling, treating and designing of future trials for these high-risk patients.

Differential expression of CD40 and CD95 in ovarian carcinoma.

PURPOSE: The role of CD95 (Fas) as a mediator of apoptosis has been well documented. CD40 ligation has been recently shown to initiate apoptosis and modulate CD95 mediated apoptosis in normal and some neoplastic tissues. Here we report the expression of CD95 and CD40 in cryopreserved cell suspensions from ovarian cancer associated ascites, fresh primary and recurrent ovarian carcinoma (OVCA) specimens, and ten established ovarian cancer cell lines. The effect of CD95 and CD40 receptor binding on apoptosis is described in two cell lines. EXPERIMENTAL DESIGN: Ascites specimens, fresh primary and recurrent OVCA specimens were dissociated to single cell suspensions. Expression of CD95 and CD40 was analyzed using flow cytometry. Apoptosis was determined via annexin uptake by flow cytometry following incubation with anti-CD95 antibody, CH11 and trimeric CD40L. RESULTS: Ascites showed the highest expression of both CD95 and CD40. Recurrent OVCA, in contrast, expressed low levels of CD95 and CD40. Primary OVCA showed moderate expression of both receptors. CD40 expression in ascites was significantly greater when compared to solid specimens (p < 0.05). Both CD40 and CD95 were strongly expressed in eight of ten cell lines studied. Binding of CD40L did not influence CD95 mediated apoptosis. CONCLUSIONS: CD40 is ubiquitously expressed in ovarian carcinomas and expression differs between ascites and solid tumor. There may be differential expression of both CD40 and CD95 in recurrent vs primary ovarian carcinoma, which may contribute to increased clinical malignancy of recurrent disease. In contrast to other epithelial malignancies, CD40 ligation does not appear to modulate CD95 mediated apoptosis.

A new approach to enhancement of bone formation by electrically polarized hydroxyapatite.

An electrical field may affect osteogenesis. Since we found that hydroxyapatite (HA) ceramics may be polarizable, we hypothesized that electrically polarized HA may foster production of new bone in vivo. Both polarized and non-polarized HA ceramics were inserted into the subperiosteum spaces at the parietal bone area of rats. After 2, 4, and 8 weeks, the implant sites were examined histologically. Morphometric analysis revealed that new bone formation was accelerated on the negatively charged surface of the polarized HA (N-surface) at 2 weeks. The newly formed bone approached maturation at 4 weeks and was thicker on the N-surface than in the controls. By 8 weeks, newly formed bone in the controls was almost the same as that on the N-surface. These findings suggest that polarized HA is biocompatible and that bone formation on the N-surface is enhanced in the early stage of bone healing.

Effect of 17á-estradiol or alendronate on the bone densitometry, bone histomorphometry and bone metabolism of ovariectomized rats

The objective of the present study was to evaluate the effect of 17á-estradiol or alendronate in preventing bone loss in 3-month-old ovariectomized Wistar rats. One group underwent sham ovariectomy (control, N = 10), and the remaining three underwent double ovariectomy. One ovariectomized group did not receive any treatment (OVX, N = 12). A second received subcutaneous 17á-estradiol at a dose of 30 æg/kg for 6 weeks (OVX-E, N = 11) and a third, subcutaneous alendronate at a dose of 0.1 mg/kg for 6 weeks (OVX-A, N = 8). Histomorphometry, densitometry, osteocalcin and deoxypyridinoline measurements were applied to all groups. After 6 weeks there was a significant decrease in bone mineral density (BMD) at the trabecular site (distal femur) in OVX rats. Both alendronate and 17á-estradiol increased the BMD of ovariectomized rats, with the BMD of the OVX-A group being higher than that of the OVX-E group. Histomorphometry of the distal femur showed a decrease in trabecular volume in the untreated group (OVX), and an increase in the two treated groups, principally in the alendronate group. In OVX-A there was a greater increase in trabecular number. An increase in trabecular thickness, however, was seen only in the OVX-E group. There was also a decrease in bone turnover in both OVX-E and OVX-A. The osteocalcin and deoxypyridinoline levels were decreased in both treated groups, mainly in OVX-A. Although both drugs were effective in inhibiting bone loss, alendronate proved to be more effective than estradiol at the doses used in increasing bone mass

Effect of 17beta-estradiol or alendronate on the bone densitometry, bone histomorphometry and bone metabolism of ovariectomized rats.

The objective of the present study was to evaluate the effect of 17beta-estradiol or alendronate in preventing bone loss in 3-month-old ovariectomized Wistar rats. One group underwent sham ovariectomy (control, N = 10), and the remaining three underwent double ovariectomy. One ovariectomized group did not receive any treatment (OVX, N = 12). A second received subcutaneous 17beta-estradiol at a dose of 30 microg/kg for 6 weeks (OVX-E, N = 11) and a third, subcutaneous alendronate at a dose of 0.1 mg/kg for 6 weeks (OVX-A, N = 8). Histomorphometry, densitometry, osteocalcin and deoxypyridinoline measurements were applied to all groups. After 6 weeks there was a significant decrease in bone mineral density (BMD) at the trabecular site (distal femur) in OVX rats. Both alendronate and 17beta-estradiol increased the BMD of ovariectomized rats, with the BMD of the OVX-A group being higher than that of the OVX-E group. Histomorphometry of the distal femur showed a decrease in trabecular volume in the untreated group (OVX), and an increase in the two treated groups, principally in the alendronate group. In OVX-A there was a greater increase in trabecular number. An increase in trabecular thickness, however, was seen only in the OVX-E group. There was also a decrease in bone turnover in both OVX-E and OVX-A. The osteocalcin and deoxypyridinoline levels were decreased in both treated groups, mainly in OVX-A. Although both drugs were effective in inhibiting bone loss, alendronate proved to be more effective than estradiol at the doses used in increasing bone mass.

Susceptibility of B-cell lymphoma to human antibodies encoded by the V4-34 gene.

Our previous studies have shown that mAbs derived from the human V4-34 gene bind and kill human B-lymphocytes via membrane disruption. This study demonstrates the cytotoxicity of two V4-34 encoded mAbs, 216 and Z2D2, towards human B-cell lymphoma. In vitro, 216 and Z2D2 are cytotoxic to a variety of B-cell lymphomas obtained from patient biopsies. In vivo, increased survival was observed with both mAbs in a lymphoma model developed in scid mice with human B-cell line Nalm-6. Studies in mice show that these mAbs are well tolerated with minimum side effects. Since 216 and Z2D2 show increased toxicity towards cycling cells, V4-34 mAb-based therapy can be additive with drugs that block cell-cycle progression. Stem cells that are V4-34 mAb ligand negative would not be depleted. Together, these studies recommend an evaluation of the two completely human mAbs in a phase I trial for B-cell lymphoma.

Treatment of high-risk uterine cancer with whole abdominopelvic radiation therapy.

PURPOSE: To evaluate the treatment outcomes in patients with optimally debulked Stage III and IV endometrial adenocarcinoma (ACA) or Stages I-IV uterine papillary serous (UPSC) or clear cell (CCC) carcinoma of the uterus, treated postoperatively with whole abdominopelvic irradiation (WAPI). METHODS AND MATERIALS: Between 1979 and 1998, 48 patients received postoperative WAPI at our institution. Twenty-two patients had FIGO Stage III or Stage IV ACA and 26 patients had FIGO Stages I-IV UPSC or CCC. The median dose was 30 Gy to the upper abdomen and 49.8 Gy to the pelvis. Mean follow-up was 37 months (2.4-135 months). RESULTS: The 3-year estimated disease-free survival (DFS) and overall survival (OS) rates for the entire group were 60% and 77%, respectively. Patients with ACA had 3-year DFS and OS of 79% and 89%, respectively, compared with 47% and 68% in the UPSC/CCC group. Early-stage patients (I and II) with UPSC/CCC had 3-year DFS and OS of 87% compared with 32% and 61% in those with advanced (Stage III and IV) disease. The 3-year actuarial major complication rate was 7%, with no treatment-related deaths. All 4 failures in the ACA group were extra-abdominal and 6 of the 11 in the UPSC/CCC group had an extra-abdominal component. Age and UPSC/CCC histology were significant prognostic factors for DFS and OS. In addition, stage and number of extrauterine sites of disease were significant predictors for DFS in UPSC/CCC. CONCLUSION: WAPI is a safe, effective treatment for patients with optimally debulked advanced-stage uterine ACA or early-stage UPSC/CCC. Survival was significantly worse in advanced-stage UPSC/CCC patients. We recommend future trials of WAPI with concurrent, or subsequent systemic therapy in patients with advanced-stage UPSC or CCC.

Recognition of auto- and exoantigens by V4-34 gene encoded antibodies.

The antigenic specificities of 24 V4-34-encoded monoclonal antibodies were compared with the amino acid sequence. The specificities were divided into three categories, red blood cells, B lymphocytes and auto/exoantigens. Six anti-I monoclonal antibodies, with multiple substitutions in their VH region, did not bind B lymphocytes or auto/exoantigens. Reactivity to these two antigens segregated with the 16 anti-i monoclonal antibodies, which were derived from the near germline V4-34 gene. All anti-i monoclonal antibodies bound B lymphocytes, albeit with varying intensities. B-cell binding correlated with basic amino acids in the VH-CDR3. Reactivity to auto/exoantigens was demonstrated only by a subset anti-i monoclonal antibodies and did not correlate with B-lymphocyte or i-antigen binding. These anti-ssDNA reactive monoclonal antibodies had basic amino acids in the VH-CDR3, strongly supporting the suggested role of arginine in DNA binding. However, an arginine-rich CDR3 was not enough to ensure DNA reactivity, since six other anti-i monoclonal antibodies that fulfilled this criteria did not bind ssDNA. Thus it is possible that the anti-DNA reactivity of V4-34-encoded monoclonal antibodies is mediated by the classic antigen-binding groove generated by the CDRs of the heavy/light chains. In contrast, anti-B-cell/i-antigen reactivity is mediated, unconventionally, by the V4-34 protein with a dominant influence of the VH-CDR3.

Primary leiomyosarcoma of the vagina. A case report and literature review.

Primary vaginal leiomyosarcoma is a rare tumor. We report a unique case of a 27-year-old woman with stage I, high-grade primary leiomyosarcoma of the vagina treated with surgical resection and adjuvant radiation therapy. She returned within 6 months with an abdominal-pelvic recurrence and lung metastases. The patient died of disease 9 months after diagnosis. A comprehensive review of primary vaginal leiomyosarcoma was performed and factors affecting survival were analyzed. A Medline search of the English-language literature revealed 66 previously reported cases. Forty-eight of these had follow-up data. Survival probabilities were calculated using the Kaplan-Meier method, and the effects of age, stage, grade, tumor location, and treatment modality were analyzed. Stage III and IV data were combined. The overall 5-year survival rate was 43%. Patients more than 50 years of age had a 5-year survival rate of 26% compared with 51% for those less than 40 years. Five-year survival for stage I and II tumors was 55% and 44%, respectively. Patients with stage III/IV disease had 25% survival at 18 months. No patient treated primarily with chemotherapy or radiation therapy survived beyond 36 months. In contrast, patients treated primarily with surgery had a 5-year survival rate of 57%. Only stage remained an independent predictor of survival on Cox regression analysis. We continue to recommend surgical resection as primary treatment. Exenteration may be an option for select patients, but ultimately management should continue on a case-by-case basis.

Malignant granular cell tumor of the vulva in a 17-year-old: Case report and literature review.

Granular cell tumors are uncommon soft tissue tumors. Although the majority of these tumors are benign, a rare malignant variant exists which is aggressive, with local recurrence rates up to 70% and 3-year survival rates of less than 50%. We present a case of malignant granular cell tumor of the vulva in a 17-year-old, the sixth such case to be reported at this site. She was treated with a left hemivulvectomy and ipsilateral groin node dissection followed by postoperative radiation therapy. She remains free of disease at 16 months. Patients with malignant granular cell tumor or granular cell tumor of malignant potential are best managed with wide local excision and regional lymph node dissection.

VH4-34 encoded antibodies in systemic lupus erythematosus: a specific diagnostic marker that correlates with clinical disease characteristics.

OBJECTIVE: To determine the clinical significance of elevated serum levels of VH4-34 encoded antibodies (VH4-34 Ab) with respect to the diagnosis and clinical characteristics of systemic lupus erythematosus (SLE). METHODS: Ninety-five patients with SLE and 344 controls were studied. The controls included 34 healthy individuals, 282 patients with nonautoimmune diseases, and 28 patients with autoimmune diseases other than SLE. VH4-34 Ab levels were measured by inhibition ELISA using anti-idiotope monoclonal antibody (9G4). SLE disease activity, severity, and damage were assessed by visual analog scales, Systemic Lupus Activity Measure, Lupus Severity of Disease Index, and Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. RESULTS: Fifty-two of 95 patients with SLE had elevated levels of VH4-34 Ab compared to 18 of 344 controls (5%), giving a sensitivity of 55% and a specificity of 95% for elevated VH4-34 Ab as a serologic test for SLE. The positive predictive value of elevated VH4-34 under these conditions was 74-85%. In this study, anti-dsDNA was not VH4-34 encoded. Significant correlations between VH4-34 and disease activity and severity indices were observed (r = 0.29-0.50). The relative risk for severe disease in SLE patients with VH4-34 antibody level in the highest tertile compared to the lowest tertile was 5.25. Twenty-five of 29 patients with lupus nephritis and 6 of 6 patients with central nervous system (CNS) lupus had elevated VH4-34 Ab. CONCLUSION: With a specificity of 94-95%, the VH4-34 antibody assay may prove valuable as a confirmatory diagnostic test for SLE. In patients with known SLE, serum VH4-34 Ab levels correlate with overall disease severity and activity, but not damage, and with nephritis and CNS lupus.

Clinical practice guidelines in the management of gynecologic malignancies.

The need for guidelines in managing gynecologic cancer is addressed in the first part of this article. Second, the guideline development process that enables the practitioner to judge the validity and usefulness of proffered guidelines is detailed. An important element in this discussion is an exploration of the shortcomings, either real or perceived, of the process. The last section focuses on issues relating to the implementation of guidelines and some of the obstacles that one may encounter as the programs evolve.

Cytotoxicity of murine B lymphocytes induced by human VH4-34 (VH4.21) gene-encoded monoclonal antibodies.

We have previously described specific binding and cytotoxicity of human B lymphocytes by VH4-34 gene-derived anti-i cold agglutinin (CA) mAbs. Here we demonstrate that the carbohydrate ligand recognized by human VH4-34 anti-i CA mAbs is also expressed on murine B lymphocytes. Similar to human B cells, binding of murine B lymphocytes by VH4-34-derived anti-i CA mAbs leads to rapid cytotoxicity of target cells as tested both in vitro and in vivo. Moreover, the mechanism leading to murine B cell death is also similar to human B cells, since morphologically identical membrane pores were detected within 15 min of mAb exposure by scanning electron microscopy. The conservation of the carbohydrate ligand across species provides an ideal system to study the function of human VH4-34 gene derived Abs in immune regulation.