Fine structural studies on white adipocyte differentiation

The differentiation of mammalian white adipocytes from prenatal through early postnatal periods was studied by light and electron microscopy in C57BL mice. Anatomical regions chosen for this study were the epididymal, mesometrial, mesenteric and inguinal fat pads. In each of these regions, adipocytes differentiated from fibroblast-like cells (preadipocytes) characterized by an ovoid nucleus, profiles of rough endoplasmic reticulum, microtubules, microfilaments, spherical mitochondria, and small multiple lipid inclusions. Preadipocytes of the inguinal fat pad were first observed prior to birth (17–19 days), whereas, in the other anatomical sites, these cells were not observed until one to three days postnatally. As differentiation proceeded, and as the adipocytes assumed a spherical shape, there was a progressive decrease in the amount of rough endoplasmic reticulum and microfilaments concomitant with transient glycogen storage and an increase in the size of lipid droplets. Mature unilocular adipocytes were observed in the inguinal fat pads at three days of age. On the other hand, these cells did not appear until seven days after birth in the epididymal fat pad, mesometrium and mesentery. Regardless of the anatomical region studied, the differentiation of preadipocytes to adipocytes proceeded similarly. Preadipocytes could not be distinguished from fibroblasts morphologically within the fat depots studied. Adipocytes at the mid-stages of differentiation and in all regions studied occasionally exhibited close intercellular contacts of varying morphology.     

Infection of immunodeficient horses with Sarcocystis neurona does not result in neurologic disease

Equine protozoal myeloencephalitis is a progressive neurologic disease of horses most commonly caused by infection with the apicomplexan parasite Sarcocystis neurona. Factors affecting neuroinvasion and neurovirulence have not been determined. We investigated the pathogenesis of infection with S. neurona in horses with severe combined immune deficiency (SCID). Two immunocompetent (IC) Arabian horses and two Arabian horses with SCID were infected orally with 5 x 10(5) sporocysts of S. neurona. Four IC horses and one SCID horse were infected intravenously (i.v.) with 5 x 10(8) merozoites of the WSU-1 isolate of S. neurona. Despite prolonged parasitemia and persistent infection of visceral tissues (skeletal muscle, cardiac muscle, lung, liver, and spleen) as demonstrated by PCR and culture, SCID horses did not develop neurologic signs after oral or i.v. infection. S. neurona was undetectable in the neuronal tissues of SCID horses by either PCR, immunohistochemistry, or culture. In contrast, although parasitemia was undetectable in orally infected IC horses and of only short duration in i.v. infected IC horses, four of six IC horses developed neurologic signs. S. neurona was detectable by PCR and/or culture of neural tissue but not visceral tissue of IC horses with neurologic disease. Infected SCID horses are unable to clear S. neurona from visceral tissues, but the infection does not result in neurologic signs; in contrast, IC horses rapidly control parasitemia and infection of visceral tissues but frequently experience neuroinvasion and exhibit clinical signs of neurologic disease.     

Mediation of in vivo glucose sensor inflammatory response via nitric oxide release

In vivo glucose sensor nitric oxide (NO) release is a means of mediating the inflammatory response that may cause sensor/tissue interactions and degraded sensor performance. The NO release (NOr) sensors were prepared by doping the outer polymeric membrane coating of previously reported needle-type electrochemical sensors with suitable lipophilic diazeniumdiolate species. The Clarke error grid correlation of sensor glycemia estimates versus blood glucose measured in Sprague-Dawley rats yielded 99.7% of the points for NOr sensors and 96.3% of points for the control within zones A and B (clinically acceptable) on Day 1, with a similar correlation for Day 3. Histological examination of the implant site demonstrated that the inflammatory response was significantly decreased for 100% of the NOr sensors at 24 h. The NOr sensors also showed a reduced run-in time of minutes versus hours for control sensors. NO evolution does increase protein nitration in tissue surrounding the sensor, which may be linked to the suppression of inflammation. This study further emphasizes the importance of NO as an electroactive species that can potentially interfere with glucose (peroxide) detection. The NOr sensor offers a viable option for in vivo glucose sensor development.     

Comparing the effectiveness of home visiting paraprofessionals and mental health professionals delivering a postpartum depression preventive intervention: a cluster-randomized non-inferiority clinical trial

To determine whether pregnant women receiving the Mothers and Babies group–based intervention exhibited greater depressive symptom reductions and fewer new cases of major depression than women receiving usual community-based services, and to examine whether groups run by paraprofessional home visitors and mental health professionals yielded similar depressive symptom reductions and prevention of major depression. Using a cluster-randomized design, 37 home visiting programs were randomized to usual home visiting, Mothers and Babies delivered via home visiting paraprofessionals, or Mothers and Babies delivered via mental health professionals. Baseline assessments were conducted prenatally with follow-up extending to 24 weeks postpartum. Eligibility criteria were ≥ 16 years old, ≤ 33 gestation upon referral, and Spanish/English speaking. Depressive symptoms at 24 weeks postpartum was the primary outcome. Eight hundred seventy-four women were enrolled. Neither intervention arm was superior to usual care in decreasing depressive symptoms across the sample (p = 0.401 home visiting paraprofessional vs. control; p = 0.430 mental health professional vs. control). Post hoc analyses suggest a positive intervention effect for women exhibiting mild depressive symptoms at baseline. We have evidence of non-inferiority, as the model-estimated mean difference in depressive symptoms between intervention arms (0.01 points, 95% CI: −0.79, 0.78) did not surpass our pre-specified margin of non-inferiority of two points. Although we did not find statistically significant differences between intervention and control arms, non-inferiority analyses found paraprofessional home visitors generated similar reductions in depressive symptoms as mental health professionals. Additionally, Mothers and Babies appears to reduce depressive symptoms among women with mild depressive symptoms when delivered by mental health professionals. This trial is registered on ClinicalTrials.gov (initial post: December 1, 2016; identifier: NCT02979444).

     

Peritransplant use of ultraviolet-B irradiation (UV-B) therapy is detrimental to allogeneic stem cell transplantation outcome.

Whole-body UV-B phototherapy has been used for the treatment of graft-versus-host disease (GVHD) of the skin and has systemic immunosuppressive and tolerogenic effects. We hypothesized that whole-body UV-B therapy would improve donor engraftment and decrease the incidence and severity of GVHD that is associated with decreased intensity allogeneic hematopoietic stem cell transplantation. This study tested the feasibility of using UV-B phototherapy that was initiated before grafting and continued until engraftment to determine its effect on transplantation outcome. Eight patients (median age, 55.5 years; range, 32-65 years) with hematologic malignancies were included. Allogeneic peripheral blood stem cells were obtained from matched related (n=5) or matched unrelated (n=3) donors. Conditioning regimen was fludarabine 30 mg/m2 intravenously for 5 days, cyclophosphamide 1 g/m2/d intravenously for 2 days, and equine antithymocyte globulin 30 mg/kg/d for 2 days. GVHD prophylaxis included cyclosporine, methylprednisolone, and escalating doses of narrowband UV-B (311 nm) according to skin tolerance, 3 days a week, from 10 days before to 28 days after transplantation. The conditioning regimen and the UV-B therapy were well tolerated. Two patients received all 14 prescribed UV-B treatments (cumulative doses of 2000 and 3260 mJ/cm2, respectively) and 6 patients received 8 to 13 treatments with a cumulative dose range of 528-3465 mJ/cm2. There was a rapid decrease in epidermal CD1a+ cells by day of transplantation. Myeloid engraftment was rapid. One patient had secondary engraftment failure at 3 months and another had mixed chimerism at day 100. Seven of 8 patients developed severe acute GVHD (grade III, n=5; grade IV, n=2). Six had skin involvement, 5 had gastrointestinal involvement, and 1 had liver involvement. Four patients died (2 from sepsis, 1 from acute GVHD, and 1 from chronic GVHD). Four patients are alive (130-287 days), 3 with extensive chronic GVHD. We conclude that extended peritransplant UV-B therapy at the standard minimally erythemogenic dose is detrimental to the outcome of allogeneic stem cell transplantation. It is unclear how UV-B at this immunsuppressive dose might have altered skin and systemic cytokine and immune cell compositions in the host and increased GVHD- and treatment-related mortalities. Different UV-B dose and schedules should be further explored. However, although other phototherapeutic modalities may be effective against GVHD, extended UV-B therapy should not be used during early phases of decreased conditioning allogeneic transplantation.     

Transplantation of hematopoietic stem cells for induction of unresponsiveness to organ allografts

Although it has been recognized since the early days of Owen and Medawar that engraftment of donor stem cells, induced in utero spontaneously or intentionally neonatally, results in life-long unresponsiveness to donor alloantigens. However, successful induction of transplantation tolerance in adult life still represents an unsolved problem. Engraftment of donor stem cells using conventional modalities involves intensive myeloablative or lymphoablative immunosuppression, which is associated with toxicity and mortality and such methods are not suitable for organ allograft recipients. In this chapter, we present an innovative approach for induction of donor-specific unresponsiveness to bone marrow and organ allografts without myeloablative conditioning. Our methods is based on cyclophosphamide-induced, alloantigen-primed lymphocyte depletion. Cyclophosphamide is administered 1 day following infusion of donor hematopoietic cells, thus eliminating predominantly host T lymphocytes reacting against donor cell challenge, and resulting in relative unresponsiveness to donor alloantigens. Subsequently, life-long tolerance to fully mismatched donor skin allografts can be accomplished by a second infusion of stem cells from the same donor, with donor T cells displacing residual alloreactive host cells that may have escaped deletion. Taken together, we believe that induction of true permanent and specific tolerance to organ allografts using donor hematopoietic cells could become a clinical reality in the foreseeable future.     

Familial translocation t(10;14) (q26.1;q32.3): report of three offspring with 10q deletion and 14q duplication

We describe two brothers and a cousin with common clinical features, including mild mental retardation, motor delays, hypotonia with truncal ataxia, esotropia, and mild facial and hand dysmorphia. The initial routine chromosome study failed to detect any abnormality in the proband. Based on a high index of clinical suspicion, high-resolution chromosome studies were performed on the proband's parents. A small reciprocal translocation t(10;14) (q26.1;q32.3) was detected in the father. The breakpoint on the derivative chromosome 14 was further placed telomeric to the immunoglobulin heavy-chain gene cluster at the band q32.33 by fluorescence in situ hybridization. Studies of the proband and two affected paternal cousins revealed that each had inherited the same derivative chromosome 10 from their carrier parents. This unbalanced karyotype resulted from an adjacent-1 segregation of the 10;14 translocation.