A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

The role of Notch signaling in human cervical cancer: implications for solid tumors

The detection of intracellular forms of Notch1 in human cervical cancers more than a decade ago prompted an investigation into the possible role of this pathway in driving these cancers. These tumors are consistently characterized by features of deregulated ligand-dependent signaling. Although Notch signaling complements the function of papillomavirus oncogenes in transformation assays of human keratinocytes, there are dose-dependent effects, which inhibit growth of established cervical cancer cell lines. Two pro-oncogenic effector mechanisms that have been suggested to operate in this context by Notch signaling are the activation of PI3K/Akt pathway and the upregulation of c-Myc. Collectively, there is a complex interplay between Notch signaling and papillomaviruses in the context of cervical carcinogenesis. Better animal model systems and identification of human cervical cancer stem cells should help clarify the possible stage specific and pleiotropic effects and regulation of Notch signaling.

Trichosporon beigelii peritonitis in a HIV-positive patient on continuous ambulatory peritoneal dialysis

Peritonitis, the commonest complication of peritoneal dialysis, is usually bacterial in origin. Fungal peritonitis is rarely encountered. We are reporting a rare case of fungal peritonitis caused by Trichosporon beigelii in a patient on continuous ambulatory peritoned dialysis (CAPD), who was HIV positive.

The contribution of mechanoreceptive neurones in the gingival tissues to the masticatory-parotid salivary reflex in man

The masticatory-parotid salivary reflex has been studied in fully dentate subjects. Salivary flow was recorded by siting a modified Lashley cup over the orifice of the parotid duct on one side of the mouth. Subjects chewed on small pieces of silicone rubber for 1-min periods which resulted in a reflex secretion of parotid saliva. The secretion was greatest when the subject chewed on the same side of the mouth (ipsilateral) as the salivary flow was recorded. Less salivary flow resulted when the subjects chewed on the opposite side of the mouth (contralateral). Selected areas of the buccal or lingual gingival tissues were then anaesthetized on the side ipsilateral to the Lashley cup. Anaesthesia of the lingual and buccal gingival tissues together resulted in a reduction of salivary flow in response to similar chewing cycles. Anaesthesia of the lingual gingival tissues alone also resulted in a reduction of salivary flow, but anaesthesia of the buccal gingival tissues alone did not. During mastication it is likely that mechanoreceptors in the gingival tissues will be stimulated which may result in salivary flow. This requires further study as other mechanoreceptive neurones are also known to be involved in the masticatory-parotid salivary reflex.

Known type 2 diabetes mellitus among the Kuwaiti population. A prevalence study

The reported prevalence of type 2 diabetes among the Kuwaiti population varied from one source to another. This study was undertaken to define the magnitude of the problem and to suggest plans for future diabetic care. All type 2 Kuwaiti diabetic subjects registered and continuing to attend regularly in two health areas Mubarak Health Area (MHA) and Farwania Health Area (FHA)] were selected for the study. There were 3222 in MHA and 5114 in FHA among the Kuwaiti population aged 20 years and above, accounting for a total crude prevalence of 7.6% in both health areas and for a prevalence rate of 5.6% in MHA and 10.0% in FHA. The age-specific prevalence of type 2 diabetes in both areas combined rose from 2.639 per 100 population in the age group 20-39 years to 15.350% and 26.252% in the age groups 40-59 and 60 and above, respectively. The female to male ratio was 1.7, 1.6, 1.1, respectively, in MHA and 1.7, 2.0, 0.9 in FHA for the age groups 20-39, 40-59, and 60 and above. This study shows that type 2 diabetes is a major public health problem in Kuwait, with a female preponderance. Obesity is a characteristic feature of the population studied, with a mean body mass index of 31.8 +/- 6.3 and 28.5 +/- 5.1 in women and men, respectively. A positive family history of diabetes mellitus was reported in 63% of the diabetic subjects. There is a need to standardize methods of reporting and to plan a national screening survey.

Polysaccharide-iron-regulated cell surface protein conjugate vaccine: its role in protection against Klebsiella pneumoniae-induced lobar pneumonia

Klebsiella pneumoniae has become an important cause of both community-acquired and nosocomial infections. In this study an attempt was made to study the immunogenicity of iron-regulated cell surface proteins (IRCSP) alone or in conjunction with the polysaccharide moiety of lipopolysaccharide (LPS) of K. pneumoniae. The polysaccharide-iron-regulated cell surface protein conjugate (PS-IRCSP) was non-toxic and non-pyrogenic. It was found to be immunogenic and the protection afforded by the conjugate against the challenge strain was observed in a rat lobar pneumonia model. The protection observed with the conjugate was higher than that observed with polysaccharide or IRCSP alone. The conjugate elicited both agglutinating and bactericidal antibodies. Enhanced phagocytosis was observed for the alveolar macrophages obtained from the lungs of animals treated with conjugate compared with macrophages obtained from animals treated with other antigenic preparations.