Post-partum hypocalcemia: idiopatic hypoparathyroidism manifested early in lactation

Hypocalcemia associated with labor and lactation is a rare condition reported previously in patients with hypovitaminosis D. We here describe a case of a young woman in whom symptomatic severe hypocalcemia appeared after her second delivery, early in lactation. At the end of lactation the condition worsened. We review all previously reported cases and suggest a possible physiologic explanation for the association between pregnancy, lactation and the appearance of symptomatic hypocalcemia.

Familial adult renal neoplasia

Our understanding of the molecular mechanisms underlying the tumorigenesis of renal cell carcinoma (RCC) has partially come from studies of RCC related familial cancer syndromes such as von Hippel-Lindau (VHL) disease and hereditary papillary RCC (HPRC). These studies have led to the identification of RCC related genes, which, besides allowing accurate diagnosis of these diseases, have been found mutated or abnormally expressed in the sporadic counterparts of these familial renal tumours. To date, a number of renal tumour related syndromes have been described. We review recent advances in this field and discuss a genetic approach to managing familial cases of renal tumours occasionally encountered by cancer geneticists and urologists.

Clinical trials in the 21st century: the case for participant-centered research

Informed consumers of the 21st century increasingly will be hesitant to enroll in randomized clinical trials (RCTs) because they will be unwilling to (a) submit to random assignment; (b) complete assessments that are too lengthy, intrusive, or irrelevant; or (c) comply with protocols that do not meet their needs. Research centered on the needs and interests of participants is likely to engender greater participation and commitment than are traditional RCTs. Recommendations for making clinical trials more participant centered include: (a) expanding our conceptualizations of study validity, (b) involving consumers as advisers in the development and execution of clinical trials, and (c) offering participants reasonable alternatives to random assignment.

Laparoscopic vs open adrenalectomy for benign adrenal neoplasm

BACKGROUND

The aim of this study was to compare the outcome of laparoscopic adrenalectomy (LA) performed for benign adrenal neoplasm to the open procedure in a similar group of patients.

METHODS

All consecutive patients who underwent LA between June 1996 and February 1999 were evaluated. Data analysis included patient's age and gender, indication for surgery, histological diagnosis, size of specimen, comorbid conditions, length of stay and ileus, postoperative narcotic consumption, and time to return to normal activity. The results were compared retrospectively to a well-matched group of patients who underwent an open adrenalectomy (OA).

RESULTS

Twenty-eight LA were performed in 24 patients for the following disorders: adrenocortical adenoma, 16 (four Cushing's syndrome, 12 Conn's syndrome); pheochromocytoma, 10; and nonfunctioning tumor, two. These cases were compared with a well-matched group of 28 patients who underwent OA in the same department. There were two conversions to open surgery (7%) in the laparoscopic group and no deaths in either group. Of all the evaluated parameters, the following statistically significant differences between the two groups were noted: The mean operative time was longer in the LA group (188 vs 139 min, p < 0.001.); however, this became insignificant in the last 10 cases of LA, when the mean length of surgery was reduced to 130 min. The overall morbidity was lower in the LA group (16% vs 39%, p = 0.05), as was the mean time to tolerate a regular diet (2 vs 3.9 days), mean meperidine consumption (mg) (109 vs 209), mean length of stay (4 vs 7.5 days), and mean time to return to normal activity (2.2 vs 5.2 weeks), (p < 0.001 for all).

CONCLUSION

LA for benign adrenal disorders is a safe procedure that is associated with significantly lower morbidity, shorter ileus and hospitalization, reduced postoperative pain, and a faster return to normal activity than the open procedure.

Magnetic resonance microscopy at 17.6-Tesla on chicken embryos in vitro

The non-destructive nature and the rapid acquisition of a three-dimensional image makes magnetic resonance microscopy (MRM) very attractive and suitable for functional imaging investigations. We explored the use of an ultra high magnetic field for MRM to increase image quality per image acquisition time. Improved image quality was characterized by a better signal-to-noise ratio (SNR), better image contrast, and higher resolution compared to images obtained at lower magnetic field strengths. Fixed chicken embryos at several stages of development were imaged at 7.0-T (300 MHz) and at 17.6-T (750 MHz). Maximum intensity projection resulted in three-dimensional vascular images with ample detail of the embryonic vasculature. We showed that at 750 MHz frequency, an image with approximately three times better SNR can be obtained by T1-weighting using a standard gadolinium contrast agent, compared to the same measurement at 300 MHz. The image contrast improved by around 20 percent and the contrast-to-noise ratio improved by almost a factor of 3.5. Smaller blood vessels of the vascular system were identified at the high field, which indicates a better image resolution. Thus, ultra high field is beneficial for MRM and opens new areas for functional imaging research, in particular when SNR, resolution, and contrast are limited by acquisition time.

Autoimmune mechanisms in antibiotic treatment-resistant lyme arthritis

In about 10% of patients with Lyme arthritis in the United States, joint inflammation persists for months or even several years after the apparent eradication of the spirochete, Borrelia burgdorferi, from the joint with antibiotic treatment. We propose a model of molecular mimicry affecting genetically susceptible individuals to explain this treatment-resistant course. The majority of patients with treatment-resistant Lyme arthritis have HLA-DRB1*0401 or related alleles, and the severity and duration of their arthritis correlate with cellular and humoral immune responses to outer-surface protein A OspA) of the spirochete. Using an algorithm, the immunodominant epitope of OspA presented by the DRB1*0401 molecule was predicted to be located at aa 165-173. In a search of the Genetics Computer Group gene bank, only one human protein was identified, lymphocyte function associated antigen-1 (hLFA-1), that had sequence homology with OspA(165-173)and predicted binding in the DRB1*0401 molecule. Synovial fluid T cells from most patients with treatment-resistant arthritis responded to both OspA and hLFA-1, whereas those from patients with other forms of chronic inflammatory arthritis did not. Molecular mimicry between a dominant T cell epitope of OspA and hLFA-1 may be an important factor in the persistence of joint inflammation in genetically susceptible patients with treatment-resistant Lyme arthritis.

[Rise of the wound surgeon to academic surgeon: myth or historical fact?]

In contrast to modern academic surgery, in 19th century German medical care was mainly taken by non-academic barber surgeons. Only after the foundation of the German Reich (1871) the practice of surgery was made conditional on a full study of medicine. The present article follows up the moot question whether the last generation of barber surgeons succeeded in rising to academic status or if the strong tradition of surgery in barber families was brought to a complete standstill. By evaluating archival documents it can be clearly shown that the professional distance between barber surgery and academic medicine was not invincible. A considerable number of barbers and their descendents (subsequently) succeeded in studying medicine and starting a medical career.

Is it the right ansatz?

This article is a response to Rasmussen et al. [Artificial Life, 7, 329-350], in which the authors suggest that, within a particular simulation "framework," there is a tight correspondence between the complexity of the primitive objects and the emergence of dynamical hierarchies. As an example they report a two-dimensional artificial chemistry that supports the spontaneous emergence of micellar structures, which they classify as third-order structures. We report in this article that essentially comparable phenomena can be produced with relatively simpler primitive objects. We also question the order classification of the micellar structures.

Magnetic resonance microscopy of mouse embryos in utero

Magnetic resonance microscopy (MRM) was used to study mouse embryonic development in utero. MRM is a non-invasive imaging technique to study normal and abnormal embryonic development. To overcome image blurring as a result of embryonic movement, fast imaging sequences were used (less than 1 min scanning time). Clear morphologic proton images were obtained by diffusion spin echo and by rapid acquisition with relaxation enhancement (RARE), revealing living mouse embryos with great anatomical detail. In addition, functional information about embryonic blood flow could be obtained, in the absence of a contrast agent. This was achieved by combining two imaging sequences, RARE and very fast gradient echo. We expect that MRM will soon become a feasible method to study longitudinally both normal and abnormal (transgenic) mouse development.

Sustained down-regulation of the epidermal growth factor receptor by decorin. A mechanism for controlling tumor growth in vivo

The small leucine-rich proteoglycan decorin interacts with the epidermal growth factor receptor (EGFR) and triggers a signaling cascade that leads to elevation of endogenous p21 and growth suppression. We demonstrate that decorin causes a sustained down-regulation of the EGFR. Upon stable expression of decorin, the EGFR number is reduced by approximately 40%, without changes in EGFR expression. However, EGFR phosphorylation is nearly completely abolished. Concurrently, decorin attenuates the EGFR-mediated mobilization of intracellular calcium and blocks the growth of tumor xenografts by down-regulating the EGFR kinase in vivo. Thus, decorin acts as an autocrine and paracrine regulator of tumor growth and could be utilized as an effective anti-cancer agent.

Recruiting families of color from the inner city: insights from the recruiters

Family interviewers hired to recruit families of color from low-income communities into a health promotion/prevention research project participated in a focus group to describe their experiences. The family interviewers described (1) recruitment techniques, (2) personal attributes they thought made a difference in their recruitment and retention efforts, (3) barriers they faced during recruitment, and (4) the experience of working for a white researcher.

Discipline across generations

The objective of this qualitative research was to understand how parents decide which discipline practices they will repeat from their childhoods. Participants chose not to repeat punishment practices when a strong, negative effect was remembered. However, some parents repeated physical punishment practices even when a strong, negative effect was remembered if they believed the practices were effective or culturally valued, if they were under stress, or if the parents lacked alternative strategies.

Threats to validity in randomized clinical trials

The purposes of this article are to present an overview of randomized clinical trials (RCTs) and describe some of the methodological problems inherent in using RCTs in nursing research. Many nursing intervention studies are fraught with problems that defy the stringent control criteria required for RCTs, leading to biased estimates of intervention efficacy. Five threats to validity in RCTs are presented, including problems related to (a) differential dropout, (b) random assignment, (c) identifying and maintaining an adequate control condition, (d) nonadherence to research protocols, and (e) assessment of clinically meaningful change. Three strategies are recommended for addressing some of the problems posed by RCTs and improving inference.