Identification of aerobic gut bacteria from the kala azar vector, Phlebotomus argentipes: a platform for potential paratransgenic manipulation of sand flies

Visceral leishmaniasis is an understudied parasitic disease responsible for significant global morbidity and mortality. We are presently investigating a method of disease prevention termed paratransgenesis. In this approach, symbiotic or commensal bacteria are transformed to produce anti-Leishmania molecules. The transformed bacteria are delivered back to sand flies to inactivate the parasite within the vector itself. In this study, we identified 28 distinct gut microorganisms from Phlebotomus argentipes trapped from four visceral leishmaniasis-endemic sites in India. A significant percent of Staphylococcus spp., environmental bacteria, and Enterobacteriaceae were identified. Two non-pathogenic organisms, Bacillus megaterium and Brevibacterium linens, were also isolated. Both organisms are also used extensively in industry. Our results indicate that B. megaterium and B. linens are possible candidates for use in a model of paratransgenesis to prevent transmission of Leishmania.

Psychological and social characteristics and precipitants of vomiting in children with cyclic vomiting syndrome

A psychological etiology or predisposition for cyclic vomiting syndrome (CVS) has long been suspected. Much of the psychiatric literature to date has blamed patients or their families for the problem or focused on psychoanalytic interpretation to account for the syndrome. Thirty-two patients with CVS were compared with 64 age- and sex-matched controls. The patients had a higher incidence of psychological symptoms and migraine. On the Achenbach Child Behavior Checklist patients had higher internalizing, somatic complaints, and anxiety/depression scores. CVS is a migraine variant, with attacks usually precipitated by stress and intercurrent infections. The psychological characteristics of patients with CVS probably contribute to their vulnerability.

Lack of prognostic significance of SPECT abnormalities in non-demented elderly subjects with memory loss

OBJECTIVE

To determine if hypoperfusion abnormalities on single photon emission computed tomography (SPECT) are associated with poorer cognitive function at baseline or increased risk of decline in cognitive function and progression to dementia in memory-impaired but non-demented elderly subjects meeting the criteria for aging associated cognitive decline (AACD).

DESIGN

Cross sectional study of 36 AACD subjects comparing hexamethyl propylene-amine oxime (HMPAO) SPECT results rated by visual inspection with base line cognitive functioning. Prospective study of these AACD subjects with clinical and neuropsychological follow-up over 35 months.

SETTING

The memory clinic and nuclear medicine unit of a university teaching hospital.

SUBJECTS

Thirty-six subjects meeting the criteria for AACD recruited from patients seen on a physician referral basis.

MAIN OUTCOME MEASURES

1) Baseline cognitive function as measured by the Mini Mental State Examination (MMSE), Boston naming, Logical Memory I subtest of the WAIS-R, and verbal fluency, correlated with SPECT status. 2) Decline in cognitive function as measured by clinical exam and the MMSE, with progression to dementia on follow-up being correlated with SPECT status at baseline.

RESULTS

18 of the 36 subjects progressed to dementia (probable Alzheimer's Disease) over follow-up. No correlation was found between the presence or absence of SPECT abnormality and MMSE or other cognitive measures. There was no correlation between the presence or absence of SPECT abnormality at initial examination, and cognitive decline according to the MMSE, or with the occurrence of clinical dementia on follow-up.

CONCLUSIONS

We conclude that SPECT abnormalities assessed by visual inspection do not correlate with severity of impairment in AACD individuals, and are not useful in predicting progression to dementia in AACD subjects.

Chronic inflammatory demyelinating polyneuropathy (CIDP) in diabetics

Seven diabetic patients developed a progressive, moderately severe, motor rather than sensory neuropathy predominantly affecting the legs. This met clinical and electrophysiological criteria for chronic inflammatory demyelinating polyneuropathy (CIDP). Nerve biopsies showed a variety of abnormalities, none of which clearly distinguished between diabetic polyneuropathy and CIDP. The patients were treated with combinations of corticosteroids, azathioprine, plasmapheresis and intravenous immune globulin; all improved substantially. We believe that CIDP may masquerade as unusually severe and progressive diabetic distal symmetric polyneuropathy. It is important to recognize CIDP in diabetics because, unlike diabetic polyneuropathy, CIDP is treatable.